KR20120095851A - Resist pattern forming method - Google Patents

Abstract

This invention is a process of (1) applying the composition for forming a resist underlayer film containing [A] polysiloxane on a board | substrate, and forming a resist underlayer film, (2) polarity is changed by the action of [a1] acid, Applying a radiation-sensitive resin composition containing a polymer having a reduced solubility to the resist underlayer film to form a resist film, (3) exposing the resist film, and (4) exposing the resist film to an organic solvent It is a resist pattern formation method which has a process of developing using the developing solution containing these.

Description

Resist pattern formation method {RESIST PATTERN FORMING METHOD}

The present invention relates to a method of forming a resist pattern.

With the miniaturization of various electronic device structures such as semiconductor devices and liquid crystal devices, miniaturization of resist patterns in lithography processes is required. At present, for example, an ArF excimer laser, which is a short wavelength radiation, and a radiation-sensitive resin composition capable of responding to such a short wavelength radiation can be used to form a fine resist pattern having a line width of about 90 nm, but in the future, Pattern formation will be required.

As a technique for enabling formation of a finer pattern by utilizing the characteristics of the radiation-sensitive resin composition, a technique of using an organic solvent having a lower polarity than an aqueous alkali solution is known as the developer (Japanese Patent Laid-Open No. 2000). -199953). As such, when the organic solvent is used, the optical contrast can be increased, and as a result, a finer pattern can be formed.

However, in the future, formation of a resist pattern of finer regions will be required. In addition, it is not only fine, but also supports formation of various resist patterns such as trench patterns such as line and space patterns and hole patterns such as contact holes, and has excellent depth of focus and pattern shape and hole patterns. There is a need for a resist pattern forming method capable of forming a resist pattern having excellent CDU (Critical Dimension Uniformity) in formation and resisting pattern collapse in trench pattern formation.

Japanese Patent Laid-Open No. 2000-199953

The present invention has been made on the basis of the above circumstances, and an object thereof is to respond to the formation of various resist patterns and to form a resist pattern excellent in depth of focus, pattern shape, resolution, CDU and pattern collapse resistance. It is to provide a pattern forming method.

The invention made to solve the above problems,

(1) A step of forming a resist underlayer film by applying the composition for forming a resist underlayer film containing [A] polysiloxane on a substrate;

(2) A radiation-sensitive resin composition containing a polymer (hereinafter also referred to as "[a1] polymer") whose polarity is changed by the action of the [a1] acid to decrease its solubility in an organic solvent, is placed on the resist underlayer film. Coating to form a resist film,

(3) exposing the resist film; and

(4) Process of developing the exposed resist film using a developing solution containing an organic solvent

It is a resist pattern formation method which has.

According to the resist pattern forming method of the present invention, by forming a resist underlayer film containing [A] polysiloxane and developing using a developer containing an organic solvent, it is possible to cope with the formation of various resist patterns. A resist pattern excellent in pattern shape, resolution, CDU, and pattern collapse resistance can be formed. Although it is not always clear why the said effect is exhibited by the said structure, for example, the pattern excellent by the strong interaction of [A] polysiloxane in the resist underlayer film formed, and the resist pattern formed on it, etc. are strong. The collapse resistance is exhibited and the pattern collapse resistance is improved, so that a wide depth of focus is exhibited, and the pattern shape, the CDU, and the resolution are considered to be improved.

The resist underlayer film forming composition

[B] Nitrogen-Containing Compounds

It may further contain.

It is thought that the crosslinking reaction in a resist underlayer film is accelerated | stimulated because the resist underlayer film formed under a resist pattern contains a nitrogen-containing compound [B], and oxygen ashing resistance can be improved.

The resist underlayer film forming composition

[C] radiation-sensitive acid generators (hereinafter also referred to as "C acid generators")

It may further contain.

It is thought that the acid dissociation reaction of the acid dissociable group in the polymer included in the resist pattern formed on the resist underlayer film is promoted by further including the [C] acid generator in the pattern formation by the organic solvent development. , Pattern collapse resistance and the like become better.

[a1] It is preferable that a polymer is a polymer which has a structural unit (I) represented by following General formula (1).

(In Formula 1, R is a hydrogen atom or a methyl group, R ^P1 , R ^P2 and R ^P3 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, provided that R ^p2 and R ^p3 are bonded to each other, May form together with a carbon atom a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms)

When the [a1] polymer in the said radiation sensitive resin composition has the said specific structural unit, since the resist pattern formed has a carboxyl group, it is thought that interaction with [A] polysiloxane in a resist underlayer film becomes stronger. As a result, the various characteristics of the resist pattern to be formed are further improved.

The radiation-sensitive resin composition

[a2] A polymer having at least one structural unit (III) selected from the group consisting of a structural unit represented by the following general formula (3-1) and a structural unit represented by the following general formula (3-2) (hereinafter " "a2" polymer ")

It is preferable to contain more.

(In formula (3-1), R <^1> is a hydrogen atom, a methyl group, or a trifluoromethyl group, R <^2> is a C1-C6 linear or branched alkyl group which has a fluorine atom, or C4 which has a fluorine atom. To a monovalent alicyclic hydrocarbon group of 20, provided that some or all of the hydrogen atoms of the alkyl group and the alicyclic hydrocarbon group may be substituted)

(In formula (3-2), R <^3> is a hydrogen atom, a methyl group, or a trifluoromethyl group, R <^4> is a (m + 1) valent coupling group, m is an integer of 1-3, and X has a fluorine atom. A divalent linking group and R ⁵ is a hydrogen atom or a monovalent organic group, provided that when m is 2 or 3, a plurality of X and R ⁵ may be the same or different, respectively)

By the radiation-sensitive resin composition containing the polymer [a2] having the specific structural unit containing a fluorine atom, the polymer [a2] is localized in its surface layer at the time of forming the resist film, and into the resist film at the time of immersion exposure. Elution of acid generators and the like into the immersion liquid is suppressed, and the hydrophobicity of the surface of the resist film is increased to enable faster scanning.

The polymer [a2] is preferably a polymer having no acid dissociable group.

When the polymer (a2) does not have an acid dissociable group, the elution suppression of an acid generator or the like during the immersion exposure described above and the hydrophobicity of the resist film surface can be further improved. Moreover, in the said resist pattern formation method using organic solvent development, even if it is a [a2] polymer which does not have an acid dissociable group, generation | occurrence | production of the development defect by a dissolution residue etc. is suppressed.

The polysiloxane (A) is preferably a hydrolysis condensate of a silane compound represented by the following general formula (i).

(In Formula (i), R ^A is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group, an aryl group or a cyano group, and part or all of the hydrogen atoms of the alkyl group are glycidyloxy groups and oxetas. May be substituted with a silyl group, an acid anhydride group or a cyano group, and some or all of the hydrogen atoms of the aryl group may be substituted with a hydroxyl group, X is a halogen atom or -OR ^B , provided that R ^B is Monovalent organic group, a being an integer of 0 to 3, provided that when R ^A and X are each plural, a plurality of R ^A and X may be the same or different.)

[A] If the polysiloxane is a hydrolyzed condensate of the specific silane compound, the interaction between the resist underlayer film formed and the resist pattern formed thereon can be enhanced, resulting in resolution of the resist pattern, resistance to pattern collapse, and the like. Can be made even better.

The resist pattern forming method preferably forms at least one pattern selected from the group consisting of trench patterns and hole patterns. As described above, according to the resist pattern forming method, since it is possible to form a pattern having excellent resolution and CDU, it is particularly preferable for forming hole patterns such as contact hole patterns, and can form patterns having excellent pattern collapse resistance. Therefore, it is especially preferable for forming trench patterns, such as a line and space pattern.

As described above, according to the resist pattern forming method of the present invention, it is possible to cope with the formation of various resist patterns, and to form a resist pattern having excellent depth of focus, pattern shape, resolution, CDU, and pattern collapse resistance.

<Method of Forming Resist Pattern>

The resist pattern forming method of the present invention,

(1) Process of forming the resist underlayer film by apply | coating the composition for resist underlayer film formation containing [A] polysiloxane on a board | substrate (henceforth "process (1)"),

(2) A step of forming a resist film by applying a radiation-sensitive resin composition containing a polymer whose polarity is changed by the action of the [a1] acid and the solubility in an organic solvent is reduced on the resist underlayer film (hereinafter, “( 2) process "),

(3) exposing the resist film (hereinafter also referred to as "(3) process"), and

(4) It has the process (henceforth "(4) process") which develops the exposed resist film using the developing solution containing an organic solvent. Hereinafter, each process is explained in full detail.

[(1) process]

In the step (1), the composition for forming a resist underlayer film containing [A] polysiloxane is applied onto a substrate to form a resist underlayer film. This resist underlayer film forming composition is mentioned later. As the substrate, a conventionally known substrate such as a silicon wafer or a wafer coated with aluminum can be used. Further, for example, an organic antireflection film disclosed in Japanese Patent Application Laid-Open No. Hei 6-12452, Japanese Patent Application Laid-Open No. 59-93448, or the like may be formed on a substrate.

As a coating method of the said composition for resist underlayer film forming, rotational coating, casting | flow_spread coating, roll coating, etc. are mentioned, for example. Moreover, as a film thickness of the resist film formed, it is 0.01 micrometer-1 micrometer normally, and 0.01 micrometer-0.5 micrometer are preferable.

After apply | coating the said composition for resist underlayer film forming, you may volatilize the solvent in a coating film by prebaking (PB) as needed. As temperature of PB, although it selects suitably according to the compounding composition of the said composition for resist underlayer film forming, it is about 50 degreeC-about 450 degreeC normally. Moreover, as PB time, it is about 5 second-about 600 second normally.

[(2) process]

In the step (2), a radiation-sensitive resin composition containing a polymer whose polarity is changed by the action of the acid [a] and the solubility in an organic solvent is reduced is applied to the resist underlayer film formed in the step (1). A resist film is formed. This radiation sensitive resin composition is mentioned later. As a coating method and coating film thickness of the said radiation sensitive resin composition, it is the same as that in the composition for resist underlayer film formation of (1) process. Moreover, as temperature of PB performed as needed, although it selects suitably according to the compounding composition of the said radiation sensitive resin composition, it is 30 degreeC-about 200 degreeC normally, and 50 degreeC-150 degreeC is preferable. Moreover, as PB time, it is about 5 second-about 600 second normally.

Further, in order to prevent the influence of basic impurities and the like contained in the environmental atmosphere, for example, a protective film disclosed in JP-A-5-188598 or the like may be provided on the resist film formed above. Moreover, in order to prevent the outflow of an acid generator etc. from a resist film, the immersion protective film currently disclosed by Unexamined-Japanese-Patent No. 2005-352384 etc. can also be provided on a resist film. In addition, these techniques can be used together.

[(3) process]

In the step (3), exposure is performed to a desired region of the resist film formed in step (2) through a mask of a specific pattern and, if necessary, the immersion liquid. This exposure may be performed several times in succession, for example, a 1st exposure may be performed to a desired area | region through a mask, and then a 2nd exposure may be performed so that it may cross | intersect the exposure part which performed the 1st exposure. For example, when a 1st exposure part and a 2nd exposure part orthogonally cross, a circular contact hole pattern will become easy to form in the unexposed part enclosed by the exposure part. Moreover, water, a fluorine-type inert liquid, etc. are mentioned as an immersion liquid used as needed at the time of exposure. The immersion liquid is preferably a liquid which is transparent with respect to the exposure wavelength and whose temperature coefficient of refractive index is as small as possible so as to minimize the distortion of the optical image projected onto the resist film, but in particular the exposure light source is an ArF excimer laser light (wavelength 193 nm). In the case of, it is preferable to use water not only in view of the above, but also in terms of availability and handling. In the case of using water, an additive which reduces the surface tension of the water and increases the surface active force may be added in a small proportion. It is preferable that this additive can disregard the influence on the optical coating on the lower surface of the lens element without dissolving the resist layer on the wafer. As water to be used, distilled water is preferable.

As radiation used for exposure, For example, electromagnetic waves, such as an ultraviolet-ray, far ultraviolet rays, X-rays, (gamma) rays; Charged particle beams, such as an electron beam and an alpha ray, etc. are mentioned. Among these, far ultraviolet rays are preferable, ArF excimer laser light and KrF excimer laser light (wavelength 248 nm) are more preferable, and ArF excimer laser light is more preferable. Exposure conditions, such as an exposure amount, are suitably selected according to the compounding composition of the said radiation sensitive resin composition, the kind of said additive, etc. When the resist pattern forming method has a plurality of exposure steps, the plurality of exposures may use the same light source or different light sources, but it is preferable to use ArF excimer laser light for the first exposure.

Moreover, it is preferable to perform post-exposure baking (PEB) after exposure. By performing PEB, dissociation reaction of the acid dissociable group of the polymer in the said radiation sensitive resin composition can be advanced smoothly. As temperature of PEB, it is 30 degreeC-200 degreeC normally, and 50 degreeC-170 degreeC is preferable. Moreover, as PEB time, it is 5 to 600 second normally.

[(4) process]

In the step (4), the pattern is formed by performing development using a developer containing an organic solvent after the exposure of the step (3). In the resist pattern forming method, the unexposed portion and the low exposed portion are selectively dissolved and removed using a developer containing an organic solvent as the developer. As a developing solution, the developing solution which has an organic solvent as a main component is preferable. As content rate of the organic solvent in a developing solution, 60 mass% or more is preferable, 70 mass% or more is more preferable, 80 mass% or more is more preferable, 90 mass% or more is especially preferable. The organic solvent contained in the developer is preferably at least one solvent selected from the group consisting of alcohol solvents, ether solvents, ketone organic solvents, amide solvents, ester organic solvents and hydrocarbon solvents.

As an alcoholic solvent, for example

Methanol, ethanol, n-propanol, iso-propanol, n-butanol, iso-butanol, sec-butanol, t-butanol, n-pentanol, iso-pentanol, 2-methylbutanol, sec-pentanol, t- Pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, sec-hexanol, 2-ethylbutanol, sec-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol , sec-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, sec-undecyl alcohol, trimethylnonyl alcohol, sec- tetradecyl alcohol, sec-heptadecyl alcohol, green Monoalcohol solvents such as furyl alcohol, phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol and diacetone alcohol;

Propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4- Polyhydric alcohol solvents such as 2-ethyl-1,3-hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol and tripropylene glycol;

Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, ethylene glycol mono-2-ethylbutyl ether, diethylene glycol mono Methyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene Polyhydric alcohol partial ether solvents such as glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, and the like.

As an ether solvent, for example

Dialiphatic ether solvents such as diethyl ether, ethyl propyl ether, dipropyl ether, dibutyl ether and diisopropyl ether;

Aromatic-containing ether solvents such as anisole, phenyl ethyl ether, phenyl propyl ether, tolyl methyl ether, tolyl ethyl ether, diphenyl ether, and tolyl ether;

Cyclic ether solvents, such as tetrahydrofuran, tetrahydropyran, and methyl tetrahydrofuran, etc. are mentioned.

As the ketone solvent, for example

Acetone, methyl ethyl ketone, methyl-n-propyl ketone, methyl-n-butyl ketone, diethyl ketone, methyl-iso-butyl ketone, methyl-n-pentyl ketone, ethyl-n-butyl ketone, methyl-n-hexyl Linear ketone solvents such as ketone, di-iso-butyl ketone and trimethyl nonnanon;

Cyclic ketone solvents such as cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone and methylcyclohexanone;

Diketone solvents such as 2,4-pentanedione and acetonyl acetone;

Hydroxyl group-containing ketone solvents such as diacetone alcohol;

Aromatic ketone solvents, such as acetophenone and phenyl ethyl ketone, etc. are mentioned.

As the amide solvent, for example

N, N'-dimethylimidazolidinone, N-methylformamide, N, N-dimethylformamide, N, N-diethylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide , N-methylpropionamide, N-methylpyrrolidone and the like.

As an ester solvent, for example

Methyl acetate, ethyl acetate, n-propyl acetate, iso-propyl acetate, n-butyl acetate, iso-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methyl acetate Pentyl, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, glycol diacetate, methoxytriglycol acetate, methyl acetoacetate, ethyl acetoacetate, propionic acid Ethyl, n-butyl propionate, iso-amyl propionate, diethyl oxalate, di-n-butyl oxalate, methyl lactate, ethyl lactate, n-butyl lactate, n-amyl lactate, diethyl malonate, dimethyl phthalate, diethyl phthalate, etc. Carboxylic acid ester solvents;

Ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol Polyhydric alcohol monoalkyl ether acetate solvents such as monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate and dipropylene glycol monoethyl ether acetate;

Carbonate solvents such as diethyl carbonate and propylene carbonate;

Lactone solvents, such as (gamma) -butyrolactone and (gamma) -valerolactone, etc. are mentioned.

As a hydrocarbon solvent, for example

aliphatic such as n-pentane, iso-pentane, n-hexane, iso-hexane, n-heptane, iso-heptane, 2,2,4-trimethylpentane, n-octane, iso-octane, cyclohexane, methylcyclohexane Hydrocarbon solvents;

Benzene, toluene, xylene, mesitylene, ethylbenzene, trimethylbenzene, methylethylbenzene, n-propylbenzene, iso-propylbenzene, diethylbenzene, iso-butylbenzene, triethylbenzene, di-iso-propylbenzene, n Aromatic hydrocarbon solvents such as amyl naphthalene;

And halogen-containing solvents such as dichloromethane, chloroform, freon, chlorobenzene, and dichlorobenzene.

Among these, alcohol solvents, ether solvents, ketone solvents and ester solvents are preferable, ether solvents, ketone solvents and ester solvents are more preferable, and aromatic-containing ether solvents, linear ketone solvents, and carboxyl. Acid ester solvents are more preferable, and n-butyl acetate, isopropyl acetate, n-butyl acetate, amyl acetate, methyl-n-pentyl ketone and anisole are particularly preferable. These organic solvents may be used individually by 1 type, and may use 2 or more types together.

 A suitable amount of surfactant can be added to a developing solution as needed. As the surfactant, for example, an ionic or nonionic fluorine-based surfactant and / or a silicone-based surfactant can be used.

As a developing method, for example, a method of immersing a substrate in a bath filled with a developing solution for a predetermined time (immersion method), a method of developing by raising a developing solution on the surface of the substrate by surface tension and stopping for a predetermined time ( Puddle method), a method of spraying a developer onto a substrate surface (spray method), and a method of continuously extracting a developer while scanning a nozzle of a developer at a constant speed on a substrate rotating at a constant speed (dynamic dispense ) Method).

In the resist pattern forming method, the resist film may be washed with a rinse liquid after the development of step (4). As a rinse liquid, an alkane solvent, a ketone solvent, an ester solvent, an alcohol solvent, an amide solvent, etc. are preferable. Among these, an alcohol solvent and an ester solvent are preferable, and a C6-C8 monovalent alcohol solvent is more preferable. Examples of the monohydric alcohol having 6 to 8 carbon atoms include linear, branched or cyclic monovalent alcohols. Examples thereof include 1-hexanol, 1-heptanol, 1-octanol, and 4-methyl-2-pentane. All, 2-hexanol, 2-heptanol, 2-octanol, 3-hexanol, 3-heptanol, 3-octanol, 4-octanol, benzyl alcohol, etc. are mentioned. Among these, 1-hexanol, 2-hexanol, 2-heptanol, 4-methyl-2-pentanol is preferable, and 4-methyl-2-pentanol is more preferable.

Each component of the said rinse liquid may be used independently and may use 2 or more types together. 10 mass% or less is preferable, as for the water content in a rinse liquid, More preferably, it is 5 mass% or less, Especially preferably, it is 3 mass% or less. By setting the water content to 10% by mass or less, good development characteristics can be obtained. Moreover, surfactant mentioned later can also be added to the rinse liquid.

Examples of the cleaning treatment include a method of continuously drawing a rinse liquid on a substrate rotating at a constant speed (rotary coating method), a method of immersing the substrate in a bath filled with the rinse liquid for a predetermined time (immersion method), a substrate The method (spray method) which sprays a rinse liquid on the surface, etc. are mentioned.

<Composition for forming a resist underlayer film>

The composition for forming a resist underlayer film used in the present invention contains [A] polysiloxane. Moreover, it is preferable that the said composition for resist underlayer film formation contains [B] nitrogen containing compound, [C] acid generator, and [D] solvent. Moreover, you may contain other arbitrary components in the range which does not impair the effect of this invention. Hereinafter, each component is demonstrated.

[[A] polysiloxane]

The polysiloxane [A] is not particularly limited as long as it is a polymer having a siloxane bond, but a hydrolyzed condensate of the silane compound represented by the general formula (i) is preferable. The silane compound used for the synthesis | combination of [A] polysiloxane may be used individually by 1 type, and may be used in combination of 2 or more type.

In said general formula (i), R ^<A> is a hydrogen atom, a fluorine atom, a C1-C5 alkyl group, an alkenyl group, an aryl group, or a cyano group. Some or all of the hydrogen atoms of the said alkyl group may be substituted by the glycidyloxy group, the oxetanyl group, the acid anhydride group, or the cyano group. Some or all of the hydrogen atoms of the aryl group may be substituted with a hydroxyl group. X is a halogen atom or -OR ^B. However, R ^B is a monovalent organic group. a is an integer of 0-3. R ^A, and when X is plural, each individual, a plurality of R ^A and X may be the same or different, respectively.

The alkyl group having 1 to 5 carbon atoms represented by the R ^A, e.g.

Linear alkyl groups such as methyl group, ethyl group, n-propyl group, n-butyl group and n-pentyl group;

And branched alkyl groups such as isopropyl group, isobutyl group, sec-butyl group, t-butyl group and isoamyl group.

As the alkenyl group represented by the above R ^A, for example, and the like groups one removing a hydrogen atom from an alkene compound, ethenyl group, 1-propene-1-yl group, 1-propene-2-yl group, 1-propen-3-yl group, 1-buten-1-yl group, 1-buten-2-yl group, 1-buten-3-yl group, 1-buten-4-yl group, 2-buten-1-yl group, 2 -Buten-2-yl group, 1-pentene-5-yl group, 2-penten-1-yl group, 2-penten-2-yl group, 1-hexene-6-yl group, 2-hexen-1-yl group, 2-hexene -2-yl group etc. are mentioned. Of these, groups represented by the following general formula (i-1) are preferable.

(In Formula (i-1), n is an integer of 0 to 4, and * represents a binding site.)

As said n, 0 or 1 is preferable and 0 (in this case, R ^A is a vinyl group) is more preferable.

The aryl group represented by R ^A, for example, a phenyl group, a naphthyl group, methylphenyl group, ethyl phenyl group, chlorophenyl group, bromophenyl group, a phenyl group, such as fluoro.

As an acid anhydride group which may substitute the said alkyl group, a succinic anhydride group, a maleic anhydride group, a glutaric anhydride group etc. are mentioned, for example.

As an alkyl group substituted by the said glycidyloxy group, 2-glycidyl oxyethyl group, 3-glycidyl oxypropyl group, 4-glycidyl oxybutyl group, etc. are mentioned, for example. Among these, 3-glycidyloxypropyl group is more preferable.

Examples of the alkyl group substituted with the oxetanyl group include 3-ethyl-3-oxetanylpropyl group, 3-methyl-3-oxetanylpropyl group, 3-ethyl-2-oxetanylpropyl group, 2 -An oxetanyl ethyl group, etc. are mentioned. Among these, 3-ethyl-3-oxetanylpropyl group is preferable.

As an alkyl group substituted by the said acid anhydride group, 2-anhydrous succinic-acid group substituted ethyl group, 3-anhydrous succinic-acid group substituted propyl group, 4-anhydrous succinic-acid group substituted butyl group, etc. are mentioned, for example. Among these, the 3-anhydride succinic acid group substituted propyl group is more preferable.

As an alkyl group substituted by the said cyano group, 2-cyanoethyl group, 3-cyanopropyl group, 4-cyanobutyl group, etc. are mentioned, for example.

As an aryl group substituted by the said hydroxyl group, 4-hydroxyphenyl group, 4-hydroxy-2-methylphenyl group, 4-hydroxy naphthyl group, etc. are mentioned, for example. Among these, 4-hydroxyphenyl group is more preferable.

As a halogen atom represented by said X, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. are mentioned.

As the monovalent organic group in the above R ^B, for example, an alkyl group, an alkylcarbonyl group and the like. As said alkyl group, a methyl group, an ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group is preferable. Moreover, as said alkylcarbonyl group, a methylcarbonyl group and an ethylcarbonyl group are preferable.

As said a, the integer of 0-2 is preferable, and 1 or 2 is more preferable.

As a specific example of the silane compound represented by the said general formula (i), it will be, for example

Phenyltrimethoxysilane, benzyltrimethoxysilane, phenethyltrimethoxysilane, 4-methylphenyltrimethoxysilane, 4-ethylphenyltrimethoxysilane, 4-methoxyphenyltrimethoxysilane, 4-phenoxyphenyl Trimethoxysilane, 4-hydroxyphenyltrimethoxysilane, 4-aminophenyltrimethoxysilane, 4-dimethylaminophenyltrimethoxysilane, 4-acetylaminophenyltrimethoxysilane, 3-methylphenyltrimethoxy Silane, 3-ethylphenyltrimethoxysilane, 3-methoxyphenyltrimethoxysilane, 3-phenoxyphenyltrimethoxysilane, 3-hydroxyphenyltrimethoxysilane, 3-aminophenyltrimethoxysilane, 3-dimethylaminophenyltrimethoxysilane, 3-acetylaminophenyltrimethoxysilane, 2-methylphenyltrimethoxysilane, 2-ethylphenyltrimethoxysilane, 2-methoxyphenyltrimethoxysilane, 2-phenoxy Cyphenyltrimethoxysilane, 2-hydroxyphenyltrimethoxysilane, 2-aminophenyltrimethoxysilane, 2- Methylaminophenyltrimethoxysilane, 2-acetylaminophenyltrimethoxysilane, 2,4,6-trimethylphenyltrimethoxysilane, 4-methylbenzyltrimethoxysilane, 4-ethylbenzyltrimethoxysilane, 4 -Methoxybenzyltrimethoxysilane, 4-phenoxybenzyltrimethoxysilane, 4-hydroxybenzyltrimethoxysilane, 4-aminobenzyltrimethoxysilane, 4-dimethylaminobenzyltrimethoxysilane, 4- Aromatic ring-containing trialkoxysilanes such as acetylaminobenzyltrimethoxysilane;

Methyltrimethoxysilane, Methyltriethoxysilane, Methyltri-n-propoxysilane, Methyltri-iso-propoxysilane, Methyltri-n-butoxysilane, Methyltri-sec-butoxysilane, Methyltri t-butoxysilane, methyltriphenoxysilane, methyltriacetoxysilane, methyltrichlorosilane, methyltriisopropenoxysilane, methyltris (dimethylsiloxy) silane, methyltris (methoxyethoxy) silane , Methyltris (methylethylketoxime) silane, methyltris (trimethylsiloxy) silane, methylsilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltri-iso-prop Foxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, ethyltri-t-butoxysilane, ethyltriphenoxysilane, ethylbistris (trimethylsiloxy) silane, ethyldichlorosilane, Ethyltriacetoxysilane, ethyltrichlorosilane, n-propyltrimethoxysilane, n-propyltri Oxysilane, n-propyltri-n-propoxysilane, n-propyltri-iso-propoxysilane, n-propyltri-n-butoxysilane, n-propyltri-sec-butoxysilane, n-propyl Tri-t-butoxysilane, n-propyltriphenoxysilane, n-propyltriacetoxysilane, n-propyltrichlorosilane, iso-propyltrimethoxysilane, iso-propyltriethoxysilane, iso-propyl Tri-n-propoxysilane, iso-propyltri-iso-propoxysilane, iso-propyltri-n-butoxysilane, iso-propyltri-sec-butoxysilane, iso-propyltri-t-butoxy Silane, iso-propyltriphenoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-butyltri-n-propoxysilane, n-butyltri-iso-propoxysilane, n- Butyltri-n-butoxysilane, n-butyltri-sec-butoxysilane, n-butyltri-t-butoxysilane, n-butyltriphenoxysilane, n-butyltrichlorosilane, 2-methylpropyl Trimethoxysilane, 2-methylpropyltrie Cysilane, 2-methylpropyltri-n-propoxysilane, 2-methylpropyltri-iso-propoxysilane, 2-methylpropyltri-n-butoxysilane, 2-methylpropyltri-sec-butoxysilane, 2-methylpropyltri-t-butoxysilane, 2-methylpropyltriphenoxysilane, 1-methylpropyltrimethoxysilane, 1-methylpropyltriethoxysilane, 1-methylpropyltri-n-propoxysilane , 1-methylpropyltri-iso-propoxysilane, 1-methylpropyltri-n-butoxysilane, 1-methylpropyltri-sec-butoxysilane, 1-methylpropyltri-t-butoxysilane, 1 -Methylpropyltriphenoxysilane, t-butyltrimethoxysilane, t-butyltriethoxysilane, t-butyltri-n-propoxysilane, t-butyltri-iso-propoxysilane, t-butyltree -n-butoxysilane, t-butyltri-sec-butoxysilane, t-butyltri-t-butoxysilane, t-butyltriphenoxysilane, t-butyltrichlorosilane, t-butyldichlorosilane, etc. Alkyltrialkoxysilanes;

Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-propoxysilane, vinyltriisopropoxysilane, vinyltri-n-butoxysilane, vinyltri-sec-butoxysilane, vinyltri-t -Butoxysilane, vinyltriphenoxysilane, allyltrimethoxysilane, allyltriethoxysilane, allyltri-n-propoxysilane, allyltriisopropoxysilane, allyltri-n-butoxysilane, allyltri alkenyltrialkoxysilanes such as -sec-butoxysilane, allyltri-t-butoxysilane and allyltriphenoxysilane;

Tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-iso-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-t-butoxysilane, etc. Tetraalkoxysilanes;

Tetraarylsilanes such as tetraphenoxysilane;

Epoxy group-containing silanes such as oxetanyltrimethoxysilane, oxiranyltrimethoxysilane, oxiranylmethyltrimethoxysilane and 3-glycidyloxypropyltrimethoxysilane;

3- (trimethoxysilyl) propyl succinic anhydride, 2- (trimethoxysilyl) ethyl succinic anhydride, 3- (trimethoxysilyl) propyl maleic anhydride, 2- (trimethoxysilyl) ethyl glutaric anhydride Acid anhydride group-containing silanes;

Tetrahalosilanes, such as tetrachlorosilane, etc. are mentioned.

Among these, tetramethoxysilane and tetraethoxysilane are preferable from the viewpoint of excellent dry etching resistance of the resulting resist underlayer film.

In addition, from the viewpoint of the reactivity of the silane compound and the ease of handling of the substance, phenyltrimethoxysilane, 4-methylphenyltrimethoxysilane, 4-methoxyphenyltrimethoxysilane, 4-methylbenzyltrimethoxysilanemethyltrimeth Methoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri-iso-propoxysilane, methyltri-n-butoxysilane, methyltri-sec-butoxysilane , Ethyltrimethoxysilane, ethyltriethoxysilane, ethyltri-n-propoxysilane, ethyltri-iso-propoxysilane, ethyltri-n-butoxysilane, ethyltri-sec-butoxysilane, n -Propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltri-n-propoxysilane, n-propyltri-iso-propoxysilane, n-propyltri-n-butoxysilane, n- Propyltri-sec-butoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane It is.

In addition, from the viewpoint of improving the pattern collapse resistance of the formed resist pattern, oxetanyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3- (trimethoxysilyl) propyl succinic anhydride, 4- Preference is given to hydroxyphenyltrimethoxysilane.

In the synthesis of the [A] polysiloxane, in addition to the silane compound represented by the general formula (i), for example,

Hexamethoxydisilane, hexaethoxydisilane, hexaphenoxydisilane, 1,1,1,2,2-pentamethoxy-2-methyldisilane, 1,1,1,2,2-pentaethoxy- 2-methyldisilane, 1,1,1,2,2-pentaphenoxy-2-methyldisilane, 1,1,1,2,2-pentamethoxy-2-ethyldisilane, 1,1, 1,2,2-pentaethoxy-2-ethyldisilane, 1,1,1,2,2-pentaphenoxy-2-ethyldisilane, 1,1,1,2,2-pentamethoxy- 2-phenyldisilane, 1,1,1,2,2-pentaethoxy-2-phenyldisilane, 1,1,1,2,2-pentaphenoxy-2-phenyldisilane, 1,1, 2,2-tetramethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraethoxy-1,2-dimethyldisilane, 1,1,2,2-tetraphenoxy-1, 2-dimethyldisilane, 1,1,2,2-tetramethoxy-1,2-diethyldisilane, 1,1,2,2-tetraethoxy-1,2-diethyldisilane, 1, 1,2,2-tetraphenoxy-1,2-diethyldisilane, 1,1,2,2-tetramethoxy-1,2-diphenyldisilane, 1,1,2,2-tetrae Oxy-1,2-diphenyldisilane, 1,1,2,2-tetraphenoxy-1,2-diphenyldisilane,

1,1,2-trimethoxy-1,2,2-trimethyldisilane, 1,1,2-triethoxy-1,2,2-trimethyldisilane, 1,1,2-triphenoxy- 1,2,2-trimethyldisilane, 1,1,2-trimethoxy-1,2,2-triethyldisilane, 1,1,2-triethoxy-1,2,2-triethyldi Silane, 1,1,2-triphenoxy-1,2,2-triethyldisilane, 1,1,2-trimethoxy-1,2,2-triphenyldisilane, 1,1,2- Triethoxy-1,2,2-triphenyldisilane, 1,1,2-triphenoxy-1,2,2-triphenyldisilane, 1,2-dimethoxy-1,1,2,2 Tetramethyldisilane, 1,2-diethoxy-1,1,2,2-tetramethyldisilane, 1,2-diphenoxy-1,1,2,2-tetramethyldisilane, 1,2 -Dimethoxy-1,1,2,2-tetraethyldisilane, 1,2-diethoxy-1,1,2,2-tetraethyldisilane, 1,2-diphenoxy-1,1,2 , 2-tetraethyldisilane, 1,2-dimethoxy-1,1,2,2-tetraphenyldisilane, 1,2-diethoxy-1,1,2,2-tetraphenyldisilane, 1, 2-diphenoxy-1,1,2,2-tetraphenyldisilane;

Bis (trimethoxysilyl) methane, bis (triethoxysilyl) methane, bis (tri-n-propoxysilyl) methane, bis (tri-isopropoxysilyl) methane, bis (tri-n-butoxysilyl Methane, bis (tri-sec-butoxysilyl) methane, bis (tri-t-butoxysilyl) methane, 1,2-bis (trimethoxysilyl) ethane, 1,2-bis (triethoxysilyl ) Ethane, 1,2-bis (tri-n-propoxysilyl) ethane, 1,2-bis (tri-isopropoxysilyl) ethane, 1,2-bis (tri-n-butoxysilyl) ethane, 1,2-bis (tri-sec-butoxysilyl) ethane, 1,2-bis (tri-t-butoxysilyl) ethane, 1- (dimethoxymethylsilyl) -1- (trimethoxysilyl) methane , 1- (diethoxymethylsilyl) -1- (triethoxysilyl) methane, 1- (di-n-propoxymethylsilyl) -1- (tri-n-propoxysilyl) methane, 1- (di Isopropoxymethylsilyl) -1- (tri-isopropoxysilyl) methane, 1- (di-n-butoxymethylsilyl) -1- (tri-n-butoxysilyl) methane, 1- (di -sec-butoxymethylsilyl) -1- (tri-sec-part Sisyl) methane, 1- (di-t-butoxymethylsilyl) -1- (tri-t-butoxysilyl) methane, 1- (dimethoxymethylsilyl) -2- (trimethoxysilyl) ethane, 1- (diethoxymethylsilyl) -2- (triethoxysilyl) ethane, 1- (di-n-propoxymethylsilyl) -2- (tri-n-propoxysilyl) ethane, 1- (di- Isopropoxymethylsilyl) -2- (tri-isopropoxysilyl) ethane, 1- (di-n-butoxymethylsilyl) -2- (tri-n-butoxysilyl) ethane, 1- (di- sec-butoxymethylsilyl) -2- (tri-sec-butoxysilyl) ethane, 1- (di-t-butoxymethylsilyl) -2- (tri-t-butoxysilyl) ethane,

Bis (dimethoxymethylsilyl) methane, bis (diethoxymethylsilyl) methane, bis (di-n-propoxymethylsilyl) methane, bis (di-isopropoxymethylsilyl) methane, bis (di-n-part Methoxymethylsilyl) methane, bis (di-sec-butoxymethylsilyl) methane, bis (di-t-butoxymethylsilyl) methane, 1,2-bis (dimethoxymethylsilyl) ethane, 1,2-bis (Diethoxymethylsilyl) ethane, 1,2-bis (di-n-propoxymethylsilyl) ethane, 1,2-bis (di-isopropoxymethylsilyl) ethane, 1,2-bis (di-n -Butoxymethylsilyl) ethane, 1,2-bis (di-sec-butoxymethylsilyl) ethane, 1,2-bis (di-t-butoxymethylsilyl) ethane, bis (dimethylmethoxysilyl) methane , Bis (dimethylethoxysilyl) methane, bis (dimethyl-n-propoxysilyl) methane, bis (dimethyl-isopropoxysilyl) methane, bis (dimethyl-n-butoxysilyl) methane, bis (dimethyl-sec -Butoxysilyl) methane, bis (dimethyl-t-butoxysilyl) methane, 1,2-bis (dimethylmethoxysilyl) ethane, 1,2-bi S (dimethylethoxysilyl) ethane, 1,2-bis (dimethyl-n-propoxysilyl) ethane, 1,2-bis (dimethyl-isopropoxysilyl) ethane, 1,2-bis (dimethyl-n- Butoxysilyl) ethane, 1,2-bis (dimethyl-sec-butoxysilyl) ethane, 1,2-bis (dimethyl-t-butoxysilyl) ethane,

1- (dimethoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (diethoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (di-n-propoxymethylsilyl) -1- ( Trimethylsilyl) methane, 1- (di-isopropoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (di-n-butoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (di -sec-butoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (di-t-butoxymethylsilyl) -1- (trimethylsilyl) methane, 1- (dimethoxymethylsilyl) -2- ( Trimethylsilyl) ethane, 1- (diethoxymethylsilyl) -2- (trimethylsilyl) ethane, 1- (di-n-propoxymethylsilyl) -2- (trimethylsilyl) ethane, 1- (di-isoprop Foxymethylsilyl) -2- (trimethylsilyl) ethane, 1- (di-n-butoxymethylsilyl) -2- (trimethylsilyl) ethane, 1- (di-sec-butoxymethylsilyl) -2- ( Trimethylsilyl) ethane, 1- (di-t-butoxymethylsilyl) -2- (trimethylsilyl) ethane,

1,2-bis (trimethoxysilyl) benzene, 1,2-bis (triethoxysilyl) benzene, 1,2-bis (tri-n-propoxysilyl) benzene, 1,2-bis (tri- Isopropoxysilyl) benzene, 1,2-bis (tri-n-butoxysilyl) benzene, 1,2-bis (tri-sec-butoxysilyl) benzene, 1,2-bis (tri-t-part Methoxysilyl) benzene, 1,3-bis (trimethoxysilyl) benzene, 1,3-bis (triethoxysilyl) benzene, 1,3-bis (tri-n-propoxysilyl) benzene, 1,3 -Bis (tri-isopropoxysilyl) benzene, 1,3-bis (tri-n-butoxysilyl) benzene, 1,3-bis (tri-sec-butoxysilyl) benzene, 1,3-bis ( Tri-t-butoxysilyl) benzene, 1,4-bis (trimethoxysilyl) benzene, 1,4-bis (triethoxysilyl) benzene, 1,4-bis (tri-n-propoxysilyl) Benzene, 1,4-bis (tri-isopropoxysilyl) benzene, 1,4-bis (tri-n-butoxysilyl) benzene, 1,4-bis (tri-sec-butoxysilyl) benzene, 1 Disilanes such as, 4-bis (tri-t-butoxysilyl) benzene;

You may use other silane compounds, such as polycarbosilane, such as polydimethoxymethyl carbosilane and poly diethoxymethyl carbosilane.

As content of [A] polysiloxane in the said composition for resist underlayer film formation, 80 mass% or more is preferable with respect to the total solid in the composition for resist underlayer film formation, 90 mass% or more is more preferable, 95 mass% or more This is more preferable. In addition, the said composition for resist underlayer film formation may contain only 1 type of [A] polysiloxane, and may contain 2 or more types.

The molecular weight of polysiloxane [A] has a polystyrene reduced weight average molecular weight (Mw) by size exclusion chromatography (GPC), usually 500 to 50,000, preferably 1,000 to 30,000, and more preferably 1,000 to 15,000.

In addition, Mw in this specification uses the GPC column (two "G2000 HXL", one "G3000HXL", and one "G4000HXL") by Tosoh, and flow rate: 1.0 mL / min, elution solvent: tetrahydrofuran Column temperature: measured by gel permeation chromatography (GPC) using monodisperse polystyrene as a standard under analytical conditions of 40 ° C.

As a method of hydrolytically condensing the silane compound represented by the said general formula (i) and the other silane compound used as needed, a well-known method of hydrolytic condensation can be used.

[[B] Nitrogen-Containing Compound]

The nitrogen-containing compound (B) is a compound having a basic amino group or a compound having a group which becomes a basic amino group by the action of an acid. The nitrogen-containing compound (B) has an effect of improving characteristics such as ashing resistance of the resist underlayer film obtained from the composition for forming a resist underlayer film. This effect is considered to be because the crosslinking reaction in an underlayer film is accelerated | stimulated because a nitrogen-containing compound [B] exists in a resist underlayer film. Examples of the nitrogen-containing compound (B) include compounds used as the acid diffusion controller for the [c] acid-sensitive resin composition described later. In addition, as the nitrogen-containing compound [B], for example, at least one group selected from a nitrogen-containing compound, a hydroxyl group, a carboxyl group, and an ether group having at least one polar group and an ester group selected from a hydroxyl group and a carboxyl group The nitrogen containing compound which has, the nitrogen containing compound which has ester group, etc. are mentioned.

As a nitrogen containing compound which has the said polar group and ester group, the compound etc. which are represented by following General formula (B-1-1)-(B-1-5) are mentioned, for example.

As a nitrogen containing compound which has at least 1 sort (s) of group chosen from a hydroxyl group, a carboxyl group, and an ether group, the compound etc. which are represented by following General formula (B-2-1)-(B-2-4) are mentioned, for example. have. Moreover, as a nitrogen containing compound which has an ester group, the compound etc. which are represented by following General formula (B-3-1)-(B-3-4) are mentioned.

In said general formula (B-2-2) and (B-2-3), R is a C1-C10 alkyl group or a C3-C10 cycloalkyl group.

As the nitrogen-containing compound (B), among these, a nitrogen-containing compound having the polar group and the ester group is preferable, and the compound represented by the general formula (B-1-1) and the compound represented by the general formula (B-1-2) This is more preferable. When the nitrogen-containing compound (B) has a polar group and an ester group together, the sublimation of the nitrogen-containing compound (B) is suppressed during baking of the resist underlayer film, and the above-described effects can be sufficiently exhibited.

The nitrogen-containing compound (B) may be used alone, or may be used in combination of two or more thereof. As content of the nitrogen-containing compound [B] in the resist underlayer film forming composition, it is 30 mass parts or less with respect to 100 mass parts of [A] polysiloxane from a viewpoint of making a pattern shape favorable, Preferably it is 10 mass parts or less More preferably, it is 1 mass part or less.

[[C] acid generator]

The acid generator (C) is a compound that generates an acid by exposure. When the resist underlayer film contains the [C] acid generator in pattern formation by organic solvent development, the acid dissociation reaction contained in the polymer in the resist pattern is promoted by the catalysis of the acid generated by exposure. As a result, the resolution and pattern collapse resistance of the resist pattern are improved. As a containing form of the [C] acid generator in the said composition for resist underlayer film forming, the form of the compound (henceforth referred to as "[C] acid generator" suitably) may be mentioned later, and it is a part of polymer It may be in the inserted state, or may be in both forms.

Examples of the [C] acid generator include onium salts such as sulfonium salts, iodonium salts, and tetrahydrothiophenium salts, N-sulfonyloxyimide compounds, organic halogen compounds, disulfones, and diazomethane sulfones. Sulfone compounds; and the like.

As said sulfonium salt, it is, for example

Triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium 2-bicyclo [2.2. 1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylsulfonium 2- (3-tetracyclo [4.4.0.1 ^2.5 .1 ^7,10 ] dodecanyl) -1 , 1-difluoroethanesulfonate, triphenylsulfonium N, N'-bis (nonnafluoro-n-butanesulfonyl) imidate, triphenylsulfonium salicylate, triphenylsulfonium camphorsulfonate, Triphenylsulfonium salt compounds such as triphenylsulfonium tricyclo [3.3.1.1 ^3,7 ] decanyldifluoromethanesulfonate;

4-cyclohexylphenyldiphenylsulfoniumtrifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium perfluoro-n- Octanesulfonate, 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-cyclohexylphenyldiphenyl Sulfonium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium N, N ' 4-cyclohexylphenyl diphenylsulfonium salt compounds, such as -bis (nonafluoro-n-butanesulfonyl) imdate and 4-cyclohexylphenyl diphenyl sulfonium camphor sulfonate;

4-t-butylphenyldiphenylsulfoniumtrifluoromethanesulfonate, 4-t-butylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-t-butylphenyldiphenylsulfonium perfluoro -n-octanesulfonate, 4-t-butylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4-t -Butylphenyldiphenylsulfonium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonate, 4-t-butylphenyldiphenyl 4-t-butylphenyl diphenylsulfonium salt compounds, such as a sulfonium N, N'-bis (nonafluoro-n-butanesulfonyl) imdate and 4-t-butylphenyl diphenylsulfonium camphor sulfonate;

Tri (4-t-butylphenyl) sulfoniumtrifluoromethanesulfonate, tri (4-t-butylphenyl) sulfonium nonafluoro-n-butanesulfonate, tri (4-t-butylphenyl) sulfonium Perfluoro-n-octanesulfonate, tri (4-t-butylphenyl) sulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate , Tri (4-t-butylphenyl) sulfonium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonate, tri (4 tri (4-t- such as -t-butylphenyl) sulfonium N, N'-bis (nonnafluoro-n-butanesulfonyl) imidate and tri (4-t-butylphenyl) sulfonium camphorsulfonate Butylphenyl) sulfonium salt compound, etc. are mentioned.

As said iodonium salt, it is, for example

Diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium 2-bi Cyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, diphenyliodonium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^{7, 10} ] dodecanyl) -1,1-difluoroethanesulfonate, diphenyliodonium N, N'-bis (nonnafluoro-n-butanesulfonyl) imidate, diphenyliodonium camphorsulfonate Diphenyl iodonium salt compounds such as these;

Bis (4-t-butylphenyl) iodonium trifluoromethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) Iodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoro Roethanesulfonate, bis (4-t-butylphenyl) iodonium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfo Nate, bis (4-t-butylphenyl) iodonium N, N'-bis (nonnafluoro-n-butanesulfonyl) imdate, bis (4-t-butylphenyl) iodonium camphorsulfonate, etc. The bis (4-t- butylphenyl) iodonium salt compound etc. are mentioned.

As said tetrahydrothiophenium salt, it is, for example

1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumtrifluoromethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumnonafluoro -n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalene-1- Yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalene-1- Yl) tetrahydrothiophenium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonate, 1- (4-n-part Toxynaphthalen-1-yl) tetrahydrothiophenium N, N'-bis (nonnafluoro-n-butanesulfonyl) imidate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydroti 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium salt compounds such as offenium camphorsulfonate;

1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiopheniumtrifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium nonafluoro -n-butanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (3,5-dimethyl-4-hydroxy Phenyl) tetrahydrothiophenium-2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (3,5-dimethyl-4-hydrate Oxyphenyl) tetrahydrothiophenium 2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonate, 1- (3,5- Dimethyl-4-hydroxyphenyl) tetrahydrothiophenium N, N'-bis (nonnafluoro-n-butanesulfonyl) imidate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydro 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium salt compounds, such as a thiophenium camphor sulfonate, etc. are mentioned.

As an N-sulfonyloxyimide compound, for example

N- (trifluoromethanesulfonyloxy) succinimide, N- (nonafluoro-n-butanesulfonyloxy) succinimide, N- (perfluoro-n-octanesulfonyloxy) succinimide , N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) succinimide, N- (2- (3-tetracyclo [ 4.4.0.1 ^2,5 .1 ^7,10 ] succinimide compounds such as dodecanyl) -1,1-difluoroethanesulfonyloxy) succinimide and N- (camphorsulfonyloxy) succinimide;

N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (nonnafluoro-n-butanesulfonyloxy) bicyclo [2.2 .1] hept-5-ene-2,3-dicarboxyimide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyi Mead, N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2 , 3-dicarboxyimide, N- (2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonyloxy) bicyclo [2.2 .1] bicyclo [such as hept-5-ene-2,3-dicarboxyimide and N- (camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide 2.2.1] hept-5-ene-2,3-dicarboxyimide compounds. Among these, sulfonium salts are preferable, and triphenylsulfonium salt compounds are more preferable, triphenylsulfonium trifluoromethanesulfonate and triphenylsulfonium tricyclo [3.3.1.1 ^3,7 ] decanyldifluoromethanesulfonate More preferred. In addition, these [C] acid generators may be used individually by 1 type, and may be used in combination of 2 or more type.

As content of the [C] acid generator in the said composition for resist underlayer film forming, it is 30 mass parts or less with respect to 100 mass parts of [A] polysiloxane from a viewpoint of making a pattern shape favorable, Preferably it is 20 mass parts or less More preferably, it is 10 mass parts or less, Especially preferably, it is 1 mass part or less.

[[D] solvent]

The composition for forming a resist underlayer film usually contains the solvent [D]. As the solvent (D), for example, a known organic solvent can be used, and for example, the same solvent as the organic solvent used as the developer in the step (4) in the resist pattern formation method described above can be used. As the solvent [D], alcohol solvents and ester solvents are preferable among these organic solvents, and polyhydric alcohol partial ether solvents and polyhydric alcohol monoalkyl ether acetate solvents are more preferable, and propylene glycol monoethyl ether and propylene glycol mono Propyl ether and propylene glycol monomethyl ether acetate are more preferable.

Water may be added to the resist underlayer film forming composition. When water is added, the silicon-containing compound is hydrated, thereby improving storage stability. In addition, when water is added, curing is accelerated during film formation of the resist underlayer film, and a dense film can be obtained. As water content in the said composition for resist underlayer film forming, 0-30 mass parts is preferable with respect to 100 mass parts of [D] solvent, More preferably, it is 0.1 mass part-20 mass parts, More preferably, it is 0.2 mass part. To 15 parts by mass. When the amount of water added is too large, storage stability deteriorates, and uniformity of the coating film deteriorates.

[Other optional ingredients]

The composition for forming a resist underlayer film may further contain β-diketone, colloidal silica, colloidal alumina, an organic polymer, a surfactant, a base generator and the like as other optional components.

<The manufacturing method of the composition for resist underlayer film forming>

Although the manufacturing method of the composition for resist underlayer film forming is not specifically limited, For example, [A] polysiloxane, [B] nitrogen containing compound, [C] acid generator, and other arbitrary components are mixed as needed, and [D] It is obtained by dissolving or dispersing in a solvent. As solid content concentration of the composition for resist underlayer film forming, it is 0.5 mass%-20 mass%, Preferably they are 1 mass%-15 mass%.

<Radiation-Resistant Resin Composition>

The radiation-sensitive resin composition used in the present invention contains a polymer whose polarity is changed by the action of the [a1] acid and the solubility in an organic solvent is reduced. Moreover, as a preferable component, it may contain a polymer [a2] and a [b] radiation sensitive acid generator (henceforth also called "[b] acid generator"), and other arbitrary things, unless the effect of this invention is impaired. It may contain a component. Hereinafter, each component is explained in full detail.

[[a1] polymer]

The polymer [a1] is a polymer whose polarity is changed by the action of an acid, so that its solubility in organic solvents is reduced. As the polymer [a1], a polymer having an acid dissociable group is preferable, and a polymer having a structural unit (I) represented by the formula (1) is more preferable.

[Structural unit (I)]

Structural unit (I) is a structural unit represented by the said Formula (1).

In said Formula (1), R is a hydrogen atom or a methyl group. R ^p1 , R ^p2 and R ^p3 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms. However, R ^p2 and R ^p3 may be bonded to each other to form a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms with the carbon atoms to which they are bonded.

As a C1-C20 monovalent hydrocarbon group represented by said R <^p1> , R <^p2> and R <^p3> , a C1-C4 linear hydrocarbon group and a C4-C20 alicyclic hydrocarbon group are preferable. The "alicyclic hydrocarbon group" may be monocyclic or polycyclic, and the monocyclic alicyclic hydrocarbon group means a monocyclic group having no aromatic group, and the polycyclic alicyclic hydrocarbon group means a polycyclic group having no aromatic group. If the polymer [a1] does not have a structural unit containing an aromatic group having a strong absorption at 193 nm, the decrease in sensitivity and the deterioration of pattern shape can be suppressed.

Examples of the monocyclic alicyclic hydrocarbon group include groups derived from cyclopentane, cyclohexane, and the like. Examples of the polycyclic alicyclic hydrocarbon group include groups derived from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane and the like. In addition, when an acid dissociable group is an acid dissociable group which has an alicyclic hydrocarbon group, one part or all part of the hydrogen atom of an alicyclic hydrocarbon group may be substituted by the C1-C8 alkyl group.

As structural unit (I), the structural unit represented by following General formula (1-1)-(1-14) etc. are mentioned, for example. In addition, although only the structural unit derived from methacrylic acid ester is described in the following chemical formula, the structural unit derived from the acrylate ester which has the same structure may be sufficient (it is the same in all structural units hereafter).

Among these, the structural units represented by the general formulas (1-1), (1-3), (1-9) and (1-14) are preferable.

As a content rate of a structural unit (I) in a polymer [a1], 30 mol%-70 mol% are preferable with respect to the total structural units which comprise a polymer of [a1]. In addition, the polymer [a1] may have one or two or more structural units (I).

[Structural unit (II)]

It is preferable that the polymer [a1] has a structural unit (II) derived from an acrylate ester containing a lactone-containing group or a cyclic carbonate-containing group. The said radiation sensitive resin composition can improve the adhesiveness with respect to the board | substrate of the resist film formed, and affinity with a developing solution, when a polymer [a1] has a structural unit (II). Here, the lactone-containing group represents a cyclic group containing one ring (lactone ring) including a -O-C (O) - structure. In addition, a cyclic carbonate containing group represents the cyclic group containing one ring (cyclic carbonate ring) containing the bond represented by -O-C (O) -O-. As this structural unit (II), the structural unit etc. which are represented by following General formula (2-1)-(2-19) are mentioned, for example.

Among these, the structural unit derived from the acrylate ester containing a lactone containing group is preferable, and the structural unit represented by the said General formula (2-1) and the structural unit represented by the said General formula (2-3) are more preferable.

As content rate of a structural unit (II) in a polymer [a1], 20 mol%-70 mol% are preferable with respect to the total structural units which comprise a polymer [a1], and 30 mol%-60 mol% are more preferable. .

[Other structural units]

[a1] The polymer is derived from a (meth) acrylic acid ester having a structural unit derived from a polar group-containing (meth) acrylic acid ester such as a hydroxyl group, a carboxyl group, a cyano group, a ketone carbonyl group, or an alicyclic structure having no acid dissociation property. It may further have other structural units, such as a structural unit. As a structural unit derived from the said hydroxyl group containing (meth) acrylic acid ester, For example, the structural unit derived from (meth) acrylic acid 3-hydroxy-1-adamantyl ester, 2-hydroxyethyl (meth) acrylic acid The structural unit derived from ester can be mentioned. As a structural unit derived from the said cyano group containing (meth) acrylic acid ester, For example, the structural unit derived from (meth) acrylic acid 2-cyanomethyl-2-adamantyl ester, and (meth) acrylic acid 2-cyanoethyl The structural unit derived from ester can be mentioned. As a structural unit derived from the said ketone carbonyl group containing (meth) acrylic acid ester, For example, the structural unit derived from (meth) acrylic acid 4-oxo-1- adamantyl ester, (meth) acrylic acid 5-oxo- [2.2. 1] The structural unit derived from hept-2-yl ester, etc. are mentioned.

As a content rate of the said other structural unit in a [a1] polymer, it is 30 mol% or less normally with respect to all the structural units which comprise a [a1] polymer, and 20 mol% or less is preferable.

[[a2] polymer]

The polymer [a2] is a polymer having the structural unit (III). By the radiation-sensitive resin composition containing the polymer [a2] having the above specific structural unit containing a fluorine atom, the polymer [a2] is localized in its surface layer at the time of forming the resist film, and is released from the resist film at the time of immersion exposure. Elution of the [b] acid generator or the like into the immersion liquid is suppressed and the hydrophobicity of the surface of the resist film is increased to enable higher speed scanning.

The structural unit (III) is at least selected from the group consisting of the structural unit (III-1) represented by the general formula (3-1) and the structural unit (III-2) represented by the following general formula (3-2). It is one structural unit.

[Structural Unit (III-1)]

Structural unit (III-1) is a structural unit represented by the said General formula (3-1).

In said general formula (3-1), R <^1> is a hydrogen atom, a methyl group, or a trifluoromethyl group. R <^2> is a C1-C6 linear or branched alkyl group which has a fluorine atom, or a C4-C20 monovalent alicyclic hydrocarbon group which has a fluorine atom. However, one part or all part of the hydrogen atom of the said alkyl group and alicyclic hydrocarbon group may be substituted.

As said C1-C6 linear or branched alkyl group, a methyl group, an ethyl group, n-propyl group, n-butyl group etc. are mentioned, for example.

As said C4-C20 monovalent alicyclic hydrocarbon group, a cyclopentyl group, a cyclopentyl propyl group, a cyclohexyl group, a cyclohexyl methyl group, a cycloheptyl group, a cyclooctyl group, a cyclooctyl methyl group etc. are mentioned, for example. .

As a monomer which provides a structural unit (III-1), a trifluoromethyl (meth) acrylate, 2,2,2- trifluoroethyl (meth) acrylate, a perfluoroethyl (meth) acrylate, purple Luoro n-propyl (meth) acrylate, perfluoro i-propyl (meth) acrylate, perfluoro n-butyl (meth) acrylate, perfluoro i-butyl (meth) acrylate, perfluoro t-butyl (meth) acrylate, perfluorocyclohexyl (meth) acrylate, 2- (1,1,1,3,3,3-hexafluoro) propyl (meth) acrylate, 1- (2 , 2,3,3,4,4,5,5-octafluoro) pentyl (meth) acrylate, 1- (2,2,3,3,4,4,5,5-octafluoro) hexyl (Meth) acrylate, perfluorocyclohexylmethyl (meth) acrylate, 1- (2,2,3,3,3-pentafluoro) propyl (meth) acrylate, 1- (2,2,3 , 3,4,4,4-heptafluoro) penta (meth) acrylate, 1- (3,3,4,4,5,5,6,6,7,7,8,8,9,9 , 10,10,10- Tadecafluoro) decyl (meth) acrylate, 1- (5-trifluoromethyl-3,3,4,4,5,6,6,6-octafluoro) hexyl (meth) acrylate, etc. Can be mentioned.

As structural unit (III-1), the structural unit etc. which are represented by following General formula (3-1-1) and (3-1-2) are mentioned, for example.

R <^1> is synonymous with the said General formula (3-1) in the said General formula (3-1-1) and (3-1-2).

As a content rate of a structural unit (III-1) in a polymer [a2], 40 mol%-100 mol% are preferable with respect to the total structural units which comprise a polymer of [a2]. In addition, the polymer [a2] may have one kind or two or more kinds of the structural unit (III-1).

[Structural Unit (III-2)]

Structural unit (III-2) is a structural unit represented by the said General formula (3-2).

In said general formula (3-2), R <^3> is a hydrogen atom, a methyl group, or a trifluoromethyl group. R ⁴ is a (m + 1) valence group. m is an integer of 1-3. X is a divalent linking group having a fluorine atom. R ⁵ is a hydrogen atom or a monovalent organic group. However, when m is 2 or 3, some X and R <^5> may be the same or different, respectively.

As a (m + 1) valent coupling group represented by said R <^4> , the same thing as R <^1> in the said General formula (3-2) is mentioned, for example. Moreover, when R <^4> is a hydrocarbon group, the structure which the oxygen atom, the sulfur atom, -NR'-, the carbonyl group, -COO-, or -CONH- couple | bonded with the terminal at the X side of R <^4> may be sufficient. However, R 'is a hydrogen atom or monovalent organic group.

In the formula (3-2), as the divalent linking group represented by X, a C 1 to C 20 divalent chain hydrocarbon group having a fluorine atom is preferable. Examples of X include the structures represented by the following formulas (X-1) to (X-6).

As X, the structure represented by the said general formula (X-1) is preferable.

As said structural unit (III-2), the structural unit etc. which are represented by following General formula (3-2-1) and (3-2-2) are mentioned, for example.

In said general formula (3-2-1), R <^4> is a C1-C20 divalent linear, branched, or cyclic saturated or unsaturated hydrocarbon group. R ³ , X and R ⁵ have the same meanings as in the general formula (3-2).

In said general formula (3-2-2), R <^3> , X, R <^5> and m are synonymous with the said General formula (3-2). However, when m is 2 or 3, some X and R <^5> may be the same or different, respectively.

As a structural unit represented by the said General formula (3-2-1), the structural unit represented by the following general formula (3-2-1-1) and the following general formula (3-2-1-2), etc. are mentioned, for example. Can be. Moreover, as a structural unit represented by the said General formula (3-2-2), the structural unit represented by the following general formula (3-2-2-1), etc. are mentioned, for example.

In said general formula (3-2-1-1), (3-2-1-2), and (3-2-2-1), R <^3> is synonymous with the said general formula (3-2).

As a monomer which provides a structural unit (III), it is (meth) acrylic acid (1,1,1-trifluoro-2- trifluoromethyl-2-hydroxy-3- propyl) ester, (meth), for example. Acrylic acid (1,1,1-trifluoro-2-trifluoromethyl-2-hydroxy-4-butyl) ester, (meth) acrylic acid (1,1,1-trifluoro-2-trifluoro Methyl-2-hydroxy-5-pentyl) ester, (meth) acrylic acid (1,1,1-trifluoro-2-trifluoromethyl-2-hydroxy-4-pentyl) ester, (meth) acrylic acid 2-{[5- (1 ', 1', 1'-trifluoro-2'-trifluoromethyl-2'-hydroxy) propyl] bicyclo [2.2.1] heptyl} ester, etc. are mentioned. have.

As a content rate of a structural unit (III) in a [a2] polymer, 30 mol%-100 mol% are preferable with respect to the total structural units which comprise a [a2] polymer. In addition, the polymer [a2] may have one or two or more structural units (III).

[a2] The polymer is a “other structural unit”, a structural unit containing a lactone structure as described above for a polymer [a1], a structural unit containing an alicyclic compound to increase etching resistance, and a substrate in order to increase the solubility in a developing solution. In order to suppress reflection from, you may further have 1 or more types of structural units derived from an aromatic compound.

The polymer [a2] is preferably a polymer having no acid dissociable group. If the polymer (a2) does not have an acid dissociable group, the elution suppression of an acid generator or the like during the immersion exposure described above and the hydrophobicity of the resist film surface can be further improved. Moreover, in the said resist pattern formation method using organic solvent development, even if it is a [a2] polymer which does not have an acid dissociable group, generation | occurrence | production of the development defect by a dissolution residue etc. is suppressed.

<Synthesis method of polymer [a1] and polymer [a2]>

The polymer [a1] and the polymer [a2] can be synthesized by, for example, polymerizing a monomer that provides each of the predetermined structural units in a suitable solvent using a radical polymerization initiator.

As reaction temperature in the said superposition | polymerization, 40 degreeC-150 degreeC and 50 degreeC-120 degreeC are preferable normally. As reaction time, 1 hour-48 hours and 1 hour-24 hours are preferable normally.

As Mw of a polymer, 1,000-50,000 are preferable, 1,000-30,000 are more preferable, 1,000-10,000 are especially preferable. By setting the Mw of the polymer [a1] in the above range, there is solubility in a solvent sufficient for use as a resist, and dry etching resistance and resist pattern shape are improved.

As ratio (Mw / Mn) of Mw of a polymer and polystyrene conversion number average molecular weight (Mn) by GPC method, it is 1-3 normally, Preferably it is 1-2.

As a polystyrene conversion weight average molecular weight (Mw) by the gel permeation chromatography (GPC) method of a polymer, [a2], 1,000-50,000 are preferable, 1,000-30,000 are more preferable, 1,000-10,000 are especially preferable. When the Mw of the polymer [a2] is less than 1,000, a sufficient forward contact angle cannot be obtained. On the other hand, when Mw exceeds 50,000, there exists a tendency for the developability at the time of setting it as a resist to fall.

As Mw and Mn of a polymer [a2], it is 1-3 normally, Preferably it is 1-2.

[[b] acid generator]

The acid generator [b] contained in the radiation-sensitive resin composition generates an acid by exposure, dissociates an acid dissociable group, etc. present in the polymer [a] with this acid, and generates a polar group such as a carboxyl group. Let's do it. As a result, the solubility of the [a1] polymer in the organic solvent is reduced. As a containing form of the acid generator [b] in the said radiation sensitive resin composition, the form (henceforth "the" bb acid generator ") suitably mentioned later may be sufficient as a part of a polymer, It may be in the form of being inserted, or in the form of both.

[b] As an acid generator, an onium salt compound, a sulfonimide compound, a halogen containing compound, a diazo ketone compound, etc. are mentioned, for example. Of these acid generators, onium salt compounds are preferable.

As an onium salt compound, onium salts, such as a sulfonium salt, a tetrahydrothiophenium salt, an iodonium salt, a phosphonium salt, an N-sulfonyloxyimide compound, a diazonium salt, a pyridinium salt, etc. are mentioned, for example.

As said sulfonium salt, it is, for example

Triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, triphenylsulfonium 2-bicyclo [2.2. 1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, triphenylsulfonium camphorsulfonate, triphenylsulfonium 2- (1-adamantyl) -1,1-di Fluoroethanesulfonate, 4-cyclohexylphenyldiphenylsulfoniumtrifluoromethanesulfonate, 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate, 4-cyclohexylphenyldiphenylsulfonium Perfluoro-n-octanesulfonate, 4-cyclohexylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 4 -Cyclohexylphenyldiphenylsulfonium camphorsulfonate, 4-methanesulfonylphenyldiphenylsulfonium trifluoromethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium nonaflu Oro-n-butanesulfonate, 4-methanesulfonylphenyldiphenylsulfoniumperfluoro-n-octanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium 2-bicyclo [2.2.1] hept-2 -Yl-1,1,2,2-tetrafluoroethanesulfonate, 4-methanesulfonylphenyldiphenylsulfonium camphorsulfonate, triphenylsulfonium 1,1,2,2-tetrafluoro-6- (1-adamantanecarbonyloxy) -hexane-1-sulfonate etc. are mentioned.

As tetrahydrothiophenium salt, it is, for example

1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumtrifluoromethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumnonafluoro -n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (4-n-butoxynaphthalene-1- Yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalene-1- I) tetrahydrothiophenium camphorsulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiopheniumtrifluoromethanesulfonate, 1- (6-n-butoxynaphthalene-2 -Yl) tetrahydrothiopheniumnonafluoro-n-butanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetra Luoroethanesulfonate, 1- (6-n-butoxynaphthalen-2-yl) tetrahydrothiophenium camphorsulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium Trifluoromethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (3,5-dimethyl-4-hydroxy Phenyl) tetrahydrothiopheniumperfluoro-n-octanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium 2-bicyclo [2.2.1] hept-2- 1-1,1,2,2-tetrafluoroethanesulfonate, 1- (3,5-dimethyl-4-hydroxyphenyl) tetrahydrothiophenium camphorsulfonate, etc. are mentioned.

As iodonium salt, for example

Diphenyliodonium trifluoromethanesulfonate, diphenyliodonium nonafluoro-n-butanesulfonate, diphenyliodonium perfluoro-n-octanesulfonate, diphenyliodonium 2-bi Cyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, diphenyliodonium camphorsulfonate, bis (4-t-butylphenyl) iodoniumtrifluor Romethanesulfonate, bis (4-t-butylphenyl) iodonium nonafluoro-n-butanesulfonate, bis (4-t-butylphenyl) iodonium perfluoro-n-octanesulfonate, bis (4-t-butylphenyl) iodonium 2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonate, bis (4-t-butylphenyl) Iodonium camphor sulfonate, and the like.

As an N-sulfonyloxyimide compound, for example

N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (nonnafluoro-n-butanesulfonyloxy) bicyclo [2.2 .1] hept-5-ene-2,3-dicarboxyimide, N- (perfluoro-n-octanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyi Mead, N- (2-bicyclo [2.2.1] hept-2-yl-1,1,2,2-tetrafluoroethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2 , 3-dicarboxyimide, N- (2- (3-tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecanyl) -1,1-difluoroethanesulfonyloxy) bicyclo [2.2 .1] hept-5-ene-2,3-dicarboxyimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, etc. are mentioned. .

Among these, onium salts are preferable, and sulfonium salts are more preferable, and triphenylsulfonium 1,1,2,2-tetrafluoro-6- (1-adamantanecarbonyloxy) -hexane-1-sulfonate , 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate and triphenylsulfonium 2- (1-adamantyl) -1,1-difluoroethanesulfonate are preferable.

[b] An acid generator may be used individually by 1 type, and may use 2 or more types together. [b] As the amount of the acid generator used, in the case of the [b] acid generator, from 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer [a1] from the viewpoint of securing the sensitivity and developability as a resist, preferably Is 0.5 mass part or more and 15 mass parts or less. In this case, when the content of the [b] acid generator is less than 0.1 part by mass, the sensitivity and developability tend to be lowered. On the other hand, when the amount of the acid generator is greater than 20 parts by mass, transparency to radiation is lowered, and a desired resist pattern becomes difficult to obtain. There is this. In addition, the acid generator [b] may be contained as a structural unit in the [a1] polymer using the (meth) acrylic acid ester having the onium salt structure.

[Other optional ingredients]

The radiation-sensitive resin composition is a [c] acid diffusion controller, [d] as other optional components in addition to the polymer [a1], the polymer [a2], and the acid generator [b], without impairing the effects of the present invention. A solvent, an alicyclic skeleton containing compound, surfactant, a sensitizer, etc. can be contained.

[[c] acid diffusion controller]

The acid diffusion controller [c] controls the diffusion phenomenon of the acid generated from the acid generator [b] by exposure, and exhibits an effect of suppressing undesirable chemical reaction in the non-exposed region. The storage stability of the obtained radiation-sensitive resin composition is further improved, the resolution as a resist is further improved, and the line width change of the resist pattern due to the variation in the post-exposure delay time from exposure to development can be suppressed. A composition with very good stability is obtained. [c] The form of the free compound (hereinafter referred to as "[c] acid diffusion control agent") may be sufficient as a containing form in the said radiation sensitive resin composition of an acid diffusion control agent, and it is a part of a polymer. It may be in the form of being inserted, or in the form of both.

[c] As an acid diffusion control agent, an amine compound, an amide group containing compound, a urea compound, a nitrogen containing heterocyclic compound, etc. are mentioned, for example.

As said amine compound, For example, Mono (cyclo) alkylamines; Di (cyclo) alkylamines; Tri (cyclo) alkylamines; Substituted alkylanilines or derivatives thereof; Ethylenediamine, N, N, N ', N'-tetramethylethylenediamine, tetramethylenediamine, hexamethylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, 4, 4'-diaminobenzophenone, 4,4'-diaminodiphenylamine, 2,2-bis (4-aminophenyl) propane, 2- (3-aminophenyl) -2- (4-aminophenyl) propane , 2- (4-aminophenyl) -2- (3-hydroxyphenyl) propane, 2- (4-aminophenyl) -2- (4-hydroxyphenyl) propane, 1,4-bis (1- ( 4-aminophenyl) -1-methylethyl) benzene, 1,3-bis (1- (4-aminophenyl) -1-methylethyl) benzene, bis (2-dimethylaminoethyl) ether, bis (2-di Ethylaminoethyl) ether, 1- (2-hydroxyethyl) -2-imidazolidinone, 2-quinoxalinol, N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine , N, N, N ', N ", N" -pentamethyldiethylenetriamine, etc. are mentioned.

Examples of the amide group-containing compound include Nt-butoxycarbonyl group-containing amino compounds, Nt-amyloxycarbonyl group-containing amino compounds, formamide, N-methylformamide, N, N-dimethylformamide, acetamide, and N-. Methylacetamide, N, N-dimethylacetamide, propionamide, benzamide, pyrrolidone, N-methylpyrrolidone, N-acetyl-1-adamantylamine, isocyanuric acid tris (2-hydroxy Ethyl). Of these, Nt-butoxycarbonyl group-containing amino compounds and Nt-amyloxycarbonyl group-containing amino compounds are preferable, and Nt-butoxycarbonyl-4-hydroxypiperidine and Nt-amyloxycarbonyl-4-hydroxypi Pyridine, Nt-butoxycarbonylpyrrolidine, Nt-butoxycarbonyl-2-hydroxymethylpyrrolidine, Nt-butoxycarbonyl-2-phenylbenzimidazole are preferred.

Examples of the urea compound include urea, methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea, and tri-n. -Butylthiourea etc. are mentioned.

As said nitrogen-containing heterocyclic compound, For example, imidazole; Pyridines; Piperazines; Piperidine, piperidine, piperazine, pyrazole, pyridazine, quinoxaline, purine, pyrrolidine, piperidine, piperidine ethanol, 3-piperidino-1,2-propanediol, morpholine, 4- (4-morpholinyl) ethanol, 4-acetylmorpholine, 3- (N-morpholino) -1,2-propanediol, 1,4-dimethylpiperazine, 1,4-diazabicyclo [2.2. 2] octane.

As the acid diffusion control agent [c], a photodegradable base that is exposed to light and generates a base by exposure can also be used. As an example of a photodegradable base, there is an onium salt compound which decomposes upon exposure and loses acid diffusion controllability. As an onium salt compound, the sulfonium salt compound represented by the following general formula (c1), and the iodonium salt compound represented by the following general formula (c2) are mentioned, for example.

In the formulas (c1) and (c2), R ^a to R ^e are each independently a hydrogen atom, an alkyl group, an alkoxyl group, a hydroxyl group or a halogen atom. Z ^- and E ^- is OH ^-, R ^f -COO ^- or R ^f -SO ₃ ^- a. However, R ^f is an alkyl group, an aryl group, an alkali group or an anion represented by the following general formula (d3).

In said Formula (c3), R <^24> is a C1-C12 linear or branched alkyl group in which one part or all of the hydrogen atoms may be substituted by the fluorine atom, or C1-C12 linear or branched alkoxy Qi. u is an integer from 0 to 2.

As said photodegradable base, the compound etc. which are represented by a following formula are mentioned, for example.

Among these, triphenylsulfonium salicylate, triphenylsulfonium 10-camphorsulfonate, and triphenylsulfonium N-butyltrifluoromethylsulfonamide are preferable.

[c] The acid diffusion controller may be used alone or in combination of two or more. As content in the case where the [c] acid diffusion control body is an [c] acid diffusion control agent, less than 5 mass parts is preferable with respect to 100 mass parts of [a1] polymers. When the acid diffusion control agent content exceeds 5 parts by mass, the sensitivity as a resist tends to be lowered.

[[d] solvent]

The said radiation sensitive resin composition contains a solvent [d] normally. The solvent is not particularly limited as long as it can dissolve at least the polymer [a1], the acid generator [b] and other optional components added as necessary. Examples of the solvent [d] include alcohol solvents, ether solvents, ketone solvents, amide solvents, ester solvents, mixed solvents thereof, and the like.

As a specific example of [d] solvent, the thing similar to the organic solvent listed at the process (4) of the resist pattern formation method mentioned above is mentioned. Among these, propylene glycol monomethyl ether acetate, cyclohexanone, and (gamma) -butyrolactone are preferable. These [d] solvents may be used independently and may use 2 or more types together.

Alicyclic Skeleton-Containing Compound

The alicyclic skeleton-containing compound exhibits an effect of improving dry etching resistance, pattern shape, adhesion with a substrate, and the like.

As an alicyclic skeleton containing compound, it is, for example

Adamantane derivatives such as 1-adamantanecarboxylic acid, 2-adamantanone, and 1-adamantanecarboxylic acid t-butyl;

Deoxycholic acid esters such as deoxycholic acid t-butyl, deoxycholic acid t-butoxycarbonylmethyl, and deoxycholic acid 2-ethoxyethyl;

Litocholic acid ester, such as t-butyl lithocholate, t-butoxycarbonylmethyl lithocholic acid, and 2-ethoxyethyl lithocholic acid;

Ethyl] tetracyclo [4.4.0.1 ^2,5 .1 ^7,10 ] dodecane, 2-hydroxy-9-methoxycarbonyl (2-hydroxy-2,2- Oxo-4-oxa-tricyclo [4.2.1.0 ^3,7 ] nonane. These alicyclic skeleton containing compounds may be used independently and may use 2 or more types together.

[Example]

Although an Example demonstrates this invention concretely below, this invention is not limited to these Examples. The measuring method of each physical property value is shown below.

¹³ C-NMR Analysis

¹³ C-NMR analysis was measured using a nuclear magnetic resonance apparatus (Nihon Denshi, JNM-EX270).

[[A] Solid Concentration in Solution of Polysiloxane]

Solid content concentration (mass%) in the solution of [A] polysiloxane in a present Example is baked by baking 0.5 g of the solution containing [A] siloxane at 250 degreeC for 30 minutes, and measuring the mass of solid content in this solution. It was.

<Synthesis of [A] polysiloxane>

The silane compound used for the synthesis | combination of [A] polysiloxane is shown below.

Silane Compound (S-1): Tetramethoxysilane

Silane Compound (S-2): Phenyltrimethoxysilane

Silane Compound (S-3): 3-ethyl-3-oxetanylpropyltrimethoxysilane

Silane Compound (S-4): Methyltrimethoxysilane

Silane Compound (S-5): 3-glycidyloxypropyltrimethoxysilane

Silane compound (S-6): 3- (trimethoxysilyl) propyl succinic anhydride

Silane Compound (S-7): 4-hydroxyphenyltrimethoxysilane

Synthesis Example 1 Synthesis of Polysiloxane (A-1)

1.28 g of oxalic acid was dissolved in 12.85 g of water to prepare an aqueous oxalic acid solution. Then, to a flask containing 25.05 g of tetramethoxysilane (the silane compound (S-1)), 3.63 g of the phenyltrimethoxysilane (the silane compound (M-2)) and 57.19 g of propylene glycol monoethyl ether, The cooling tube and the dropping funnel in which the prepared oxalic acid aqueous solution were put were set. Subsequently, after heating to 60 degreeC in an oil bath, the oxalic acid aqueous solution was slowly dripped and reacted at 60 degreeC for 4 hours. After the completion of the reaction, the flask containing the reaction solution was allowed to cool, set in an evaporator, and methanol produced by the reaction was distilled off to obtain 97.3 g of a solution containing polysiloxane (A-1). Solid content concentration in the obtained polysiloxane (A-1) solution was 18.0 mass%. In addition, Mw of polysiloxane (A-1) was 2,000.

Synthesis Example 2 (Synthesis of Polysiloxane (A-2))

2.92 g of tetramethylammonium hydroxide (TMAH) was dissolved in 8.75 g of water to prepare an aqueous TMAH solution. Thereafter, a cooling tube, 10.65 g of tetramethoxysilane (the silane compound (S-1)), and phenyltrimethoxysilane (the above) were placed in a flask containing 11.67 g of an aqueous TMAH solution, 4.53 g of water and 20 g of methanol A dropping funnel containing 1.98 g of silane compound (S-2)), 2.72 g of methyltrimethoxysilane (the above silane compound (S-4)) and 20 g of methanol were set. Then, after heating to 50 degreeC in an oil bath, the methanol solution which is a monomer was dripped slowly, and it was made to react at 50 degreeC for 2 hours. After the reaction was completed, the flask containing the reaction solution was allowed to cool.

Thereafter, 4.39 g of maleic anhydride was dissolved in 16.14 g of water and 16.14 g of methanol, and 36.67 g of a maleic acid methanol solution prepared separately was added dropwise to the reaction solution and stirred for 30 minutes. Subsequently, 50 g of 4-methyl-2-pentenone was added, set in an evaporator, and the reaction solvent and methanol produced by the reaction were distilled off to obtain a 4-methyl-2-pentenone solution of polysiloxane. After the obtained solution was transferred to the separating funnel, 80 g of water was added to wash the first time, and 40 g of water was added to wash the second time. Thereafter, 50 g of propylene glycol-1-ethyl ether was added to the 4-methyl-2-pentenone solution transferred from the separating funnel to the flask, set in an evaporator, and 4-methyl-2-pentenone was distilled off to remove polysiloxane. 51 g of a solution containing (A-2) was obtained. Solid content concentration in the obtained polysiloxane (A-2) solution was 18.0 mass%. In addition, Mw of polysiloxane (A-2) was 4,000.

Synthesis Examples 3 to 10 (Synthesis of Polysiloxanes (A-3) to (A-10))

Polysiloxanes (A-3) to (A-10) were synthesized in the same manner as in Synthesis example 1, except that the silane compound of the kind and dose shown in Table 1 was used. Solid content concentration of the solution containing the obtained polysiloxane and Mw of polysiloxane are combined and shown in Table 1 with the synthesis examples 1 and 2.

<Preparation of the composition for forming a resist underlayer film>

It shows below about the [B] nitrogen containing compound, [C] acid generator, and [D] solvent other than [A] polysiloxane obtained by each said synthesis example used for manufacture of the composition for resist underlayer film forming.

[[B] Nitrogen-Containing Compound]

B-1: N-t-amyloxycarbonyl-4-hydroxypiperidine

B-2: N-t-butoxycarbonyl-4-hydroxypiperidine

[[C] acid generator]

C-1: triphenylsulfonium trifluoromethanesulfonate

C-2: triphenylsulfonium tricyclo [3.3.1.1 ^3,7 ] decanyldifluoromethanesulfonate

[[D] solvent]

D-1: Propylene Glycol Monomethyl Ether Acetate

D-2: Propylene Glycol Monoethyl Ether

D-3: propylene glycol monopropyl ether

Synthesis Example 11 (Preparation of Resin Underlayer Film Forming Composition (P-1))

9.70 parts by mass of polysiloxane (A-1) and 0.05 parts by mass of nitrogen-containing compound (B-1) were dissolved in 68.74 parts by mass of solvent (D-1) and 21.51 parts by mass of solvent (D-2). Filtration was carried out with a micrometer filter to obtain a composition for forming a resist underlayer film (P-1).

Synthesis Examples 12 to 28 (Preparation of the composition for forming a resist underlayer film (P-2) to (P-18))

Except having used each component of the kind and compounding quantity shown in following Table 2, it carried out similarly to the synthesis example 11, and manufactured the resist underlayer film formation compositions (P-2)-(P-18), respectively. "-" Of Table 2 shows that the above-mentioned component was not used.

&Lt; Preparation of radiation-sensitive resin composition >

<Synthesis of polymer [a1]>

The monomer compound used for the synthesis of the [a1] polymer is shown below.

Synthesis Example 29 (Synthesis of Polymer (a1-1))

12.9 g (50 mol%) of the compound (M-1) and 17.1 g (50 mol%) of the compound (M-2) were dissolved in 60 g of methyl ethyl ketone, and 2,2'-azobisisobutyronitrile ( AIBN) 1.77 g was added to dissolve to prepare a monomer solution. Subsequently, a 200 mL three-necked flask containing 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, then heated to 80 ° C. while stirring the reaction kettle, and the monomer solution was added dropwise over 3 hours using a dropping funnel. . The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The white powder separated by filtration was washed twice with slurry using 150 g of methanol, and the mixture was separated by filtration and dried again at 50 ° C. for 17 hours to obtain a white powder of polymer (a1-1). (Yield 80%). ^As a result of ¹³ C-NMR, the content ratio of the structural unit derived from the compound (M-1) / (M-2) in the polymer (a1-1) was 49/51 (mol%). Moreover, Mw of the polymer (a1-1) was 6,900 and Mw / Mn was 1.35.

Synthesis Example 30 (Synthesis of Polymer (a1-2))

14.1 g (50 mol%) of the compound (M-3) and 15.9 g (50 mol%) of the compound (M-2) were dissolved in 60 g of methyl ethyl ketone, and 0.5 g of AIBN was added to dissolve to prepare a monomer solution. It was. Subsequently, a 200 mL three-necked flask containing 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, then heated to 80 ° C. while stirring the reaction kettle, and the monomer solution was added dropwise over 3 hours using a dropping funnel. . The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The white powder separated by filtration was washed twice with a slurry using 150 g of methanol, and the mixture was filtered again and dried again at 50 ° C. for 17 hours to obtain a white powder of polymer (a1-2). (Yield = 76.5%). ^As a result of ¹³ C-NMR, the content ratio of the structural unit derived from the compound (M-3) / (M-2) in the polymer (a1-2) was 48/52 (mol%). Moreover, Mw of the polymer (a1-2) was 13,200 and Mw / Mn was 1.53.

Synthesis Example 31 (Synthesis of Polymer (a1-3))

Compound (M-1) 11.1 g (40 mol%), Compound (M-4) 3.9 g (10 mol%), Compound (M-6) 3.9 g (10 mol%) and Compound (M-5) 11.2 g (40 mol%) was dissolved in 60 g of methyl ethyl ketone, and a solution prepared by adding 1.3 g of AIBN was prepared. Subsequently, a 200 mL three-necked flask with 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring the reaction pot, and the prepared monomer solution was added to the dropping funnel over 3 hours. It dripped. The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The filtrated fractional white powder was washed twice with 150 g of methanol in slurry, and then filtered and dried again at 50 ° C. for 17 hours to obtain a white powdery polymer (a1-3) (Mw = 6,400). , Mw / Mn = 1.43, yield = 72.1%). The content rate of the structural unit derived from compound (M-1) / (M-4) / (M-6) / (M-5) in a polymer (a1-3) is 38/10/11/41 (mol%) Was.

Synthesis Example 32 (Synthesis of Polymer (a1-4))

12.7 g (50 mol%) of the compound (M-1), 3.9 g (10 mol%) of the compound (M-7) and 13.4 g (40 mol%) of the compound (M-2) were dissolved in 60 g of methyl ethyl ketone. To prepare a solution in which 1.2 g of AIBN was added. Subsequently, a 200 mL three-necked flask with 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring the reaction pot, and the prepared monomer solution was added to the dropping funnel over 3 hours. It dripped. The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The filtration fractionated white powder was washed twice with 150 g of methanol in slurry, and then filtered filtration and dried at 50 ° C. for 17 hours to obtain a white powder polymer (a1-4) (Mw = 5,900). , Mw / Mn = 1.42, yield = 72.3%). The content rate of the structural unit derived from compound (M-1) / (M-7) / (M-2) in the polymer (a1-4) was 48/11/41 (mol%).

Synthesis Example 33 (Synthesis of Polymer (a1-5))

12.9 g (50 mol%) of the compound (M-1), 3.6 g (10 mol%) of the compound (M-8) and 13.6 g (40 mol%) of the compound (M-2) were dissolved in 60 g of methyl ethyl ketone. To prepare a solution in which 1.3 g of AIBN was added. Subsequently, a 200 mL three-necked flask with 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring the reaction pot, and the prepared monomer solution was added to the dropping funnel over 3 hours. It dripped. The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The filtration fractionated white powder was washed twice with 150 g of methanol in slurry, and then filtered filtration and dried at 50 ° C. for 17 hours to obtain a white powder polymer (a1-5) (Mw = 57). , 00, Mw / Mn = 1.38, yield = 72.5%). The content rate of the structural unit derived from compound (M-1) / (M-8) / (M-2) in the polymer (a1-5) was 49/11/40 (mol%).

Synthesis Example 34 (Synthesis of Polymer (a1-6))

12.2 g (45 mol%) of the compound (M-3), 5.5 g (15 mol%) of the compound (M-9) and 12.3 g (40 mol%) of the compound (M-2) were dissolved in 60 g of methyl ethyl ketone. To prepare a solution in which 0.5 g of AIBN was added. Subsequently, a 200 mL three-necked flask with 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring the reaction pot, and the prepared monomer solution was added to the dropping funnel over 3 hours. It dripped. The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The filtration fractionated white powder was washed twice with 150 g of methanol in slurry, and then filtered filtration and dried at 50 ° C. for 17 hours to obtain a white powder polymer (a1-6) (Mw = 13,400). , Mw / Mn = 1.59, yield = 76.3%). The content rate of the structural unit derived from compound (M-13) / (M-19) / (M-12) in the polymer (a1-6) was 44/15/41 (mol%).

<Synthesis of polymer [a2]>

The monomer compound used for the synthesis of the [a2] polymer is shown below.

Synthesis Example 35 (Synthesis of Polymer (a2-1))

10.4 g (30 mol%) of the compound (M-10) and 19.6 g (70 mol%) of the compound (M-11) are dissolved in 60 g of methyl ethyl ketone, and 2,2'-azobis (isobutyronitrile ) 0.91 g (5 mol%) was prepared. Subsequently, a 200 mL three-necked flask with 30 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. while stirring the reaction pot, and the prepared monomer solution was added to the dropping funnel over 3 hours. It dripped. The dropping start was taken as the polymerization start time, and the polymerization reaction was carried out for 6 hours. After the completion of the polymerization, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, poured into 600 g of methanol, and the precipitated white powder was separated by filtration. The filtration fractionated white powder was washed twice with 150 g of methanol in the form of a slurry, and then filtered filtration and dried at 50 ° C. for 12 hours to obtain a white powder polymer (a2-1) (Mw = 5,900). , Mw / Mn = 1.58, yield = 68%). The content rate of the structural unit derived from (M-10) / (M-11) in the polymer (a2-1) was 31/69 (mol%).

Synthesis Example 36 (Synthesis of Polymer (a2-2))

35.8 g (70 mol%) of compound (M-12) and 14.2 g (30 mol%) of compound (M-13) are dissolved in 100 g of methyl ethyl ketone, and dimethyl 2,2'-azobisiso is used as a polymerization initiator. 3.2 g of butyrate were added to prepare a monomer solution. A 500 mL three-necked flask containing 100 g of methyl ethyl ketone was purged with nitrogen for 30 minutes, heated to 80 ° C. with stirring, and the prepared monomer solution was added dropwise over 3 hours with a dropping funnel. The dropping start was taken as the start time of the polymerization reaction, and the polymerization reaction was carried out for 6 hours. After completion of the polymerization reaction, the polymerization reaction solution was cooled with water and cooled to 30 ° C. or lower, and washed with 825 g of a methanol / methylethyl ketone / hexane = 2/1/8 (mass ratio) mixed solution, followed by propylene glycol monomethyl acetate. Solvent substitution with ether gave a solution of Polymer 8 (38.0 g, yield 76.0% in terms of solid content). ^As a result of ¹³ C-NMR analysis, the content ratio (mol%) of the structural unit derived from the compound (M-12) in the polymer (a2-2): the compound (M-13) was 70:30. It was. Moreover, Mw of the polymer (a2-2) was 7,000 and Mw / Mn was 1.40.

The components ([b] acid generator, [c] acid diffusion control agent, and [d] solvent) other than the [a1] polymer and [a2] polymer which were used for manufacture of a radiation sensitive resin composition are shown below.

[[b] acid generator]

b-1: triphenylsulfonium 1,1,2,2-tetrafluoro-6- (1-adamantanecarbonyloxy) -hexane-1-sulfonate represented by the following general formula (b-1) compound)

b-2: 4-cyclohexylphenyldiphenylsulfonium nonafluoro-n-butanesulfonate (compound represented by the following general formula (b-2))

b-3: triphenylsulfonium 2- (1-adamantyl) -1,1-difluoroethanesulfonate (compound represented by the following general formula (b-3))

[[c] acid diffusion control agents]

c-1: triphenylsulfonium salicylate (compound represented by the following general formula (c-1))

c-2: N-t-amyloxycarbonyl-4-hydroxypiperidine (compound represented by the following formula (c-2))

c-3: N-t-butoxycarbonyl-4-hydroxypiperidine (compound represented by the following formula (c-3))

c-4: triphenylsulfonium 10-camphorsulfonate (compound represented by the following formula (c-4))

c-5: N-t-butoxycarbonylpyrrolidine (compound represented by the following formula (c-5))

c-6: N-t-butoxycarbonyl-2-phenylbenzimidazole (compound represented by the following formula (c-6))

c-7: N-t-butoxycarbonyl-2-hydroxymethylpyrrolidine (compound represented by the following general formula (c-7))

c-8: triphenylsulfonium N-butyltrifluoromethylsulfonamide (compound represented by the following formula (c-8))

[[d] solvent]

d-1: propylene glycol monomethyl ether acetate

d-2: cyclohexanone

d-3: γ-butyrolactone

Synthesis Example 37 (Manufacture of Radiation-sensitive Resin Composition (J-1))

100 parts by mass of the polymer (a1-1), 3 parts by mass of the polymer (a2-1), 10.8 parts by mass of the acid generator (b-1), 4.3 parts by mass of the acid diffusion controller (c-1) and the solvent (d-1 2,185 parts by mass, 935 parts by mass of the solvent (d-2) and 30 parts by mass of the solvent (d-3) were mixed to prepare a radiation sensitive resin composition (J-1).

Synthesis Examples 38 to 50 (Preparation of Radiation Sensitive Resin Compositions (J-2) to (J-14))

Except having used each component of the kind and compounding quantity shown in Table 3, it carried out similarly to the synthesis example 37, and produced the radiation sensitive resin compositions (J-2)-(J-14), respectively.

<Characteristic evaluation of resist underlayer film>

Using the obtained resist underlayer film forming compositions (P-1) to (P-18), respectively, the resist underlayer film was formed according to the following method, and the following characteristic evaluation was performed about this resist underlayer film.

[Formation of resist underlayer film]

On the silicon wafer, the resist underlayer film forming composition (P-1) obtained in the said synthesis example 11 was apply | coated by the spin coating method. For spin coating, a coating / developing apparatus ("CLEAN TRACK ACT 12", manufactured by Tokyo Electron) was used (hereinafter, the same apparatus is used for those not specifically described). PB was performed for 1 minute on the obtained coating film by the 220 degreeC hotplate, and the resist underlayer film was formed. It was 30 nm when the film thickness of the obtained resist underlayer film was measured with the film thickness measuring apparatus ("M-2000D", J.A. Woollam).

[Characteristic evaluation]

About the obtained resist underlayer film, board | substrate reflectance, resist residue, and oxygen ashing tolerance were evaluated using the radiation sensitive resin composition (J-1) obtained by the synthesis example 37 according to the following method.

Board Reflectance

Refractive index parameter (n) and attenuation coefficient (k) with respect to the resist film obtained from the formed resist underlayer film, the antireflection film forming material ("NFC HM8006", manufactured by JSR) and the radiation-sensitive resin composition Is measured by a high-speed spectroscopic ellipsometer "M-2000" (manufactured by JAWoollam), and based on these measurements, NA 1.3, Dipole conditions using simulation software "Prolith" (manufactured by KLA-Tencor) The board | substrate reflectance of the laminated | multilayer film of the resist film / each resist underlayer film / antireflection film below was calculated | required. The case where the board | substrate reflectance is 1% or less was evaluated by "A", the case where it is more than 1% and 2% or less by "B", and the case where it exceeds 2% by "C". The evaluation results are shown in Table 4 below.

(Resist residue)

On the resist underlayer film, the radiation sensitive resin composition was apply | coated by spin coating, and PB was performed at 100 degreeC for 60 second on the hotplate, and the resist film with a film thickness of 100 nm was formed. Subsequently, after developing for 1 minute with butyl acetate without performing exposure, the film thickness of the film (resist underlayer film + resist film residue) on a board | substrate was measured. A film thickness measuring apparatus ("M-2000D", manufactured by J.A. Woollam) was used for the measurement of the film thickness (hereinafter, the same). The difference between the film thickness of the resist underlayer film before the organic solvent development and the film thickness was determined, and the resist residue (unit: nm) was measured. The measured value of the resist residue is shown in Table 4 below. In addition, when a resist residue is less than 5 nm, it can evaluate as "A", and when it is 5 nm or more, it can evaluate as "B".

(Oxygen ashing resistance)

The resist underlayer film was subjected to O ₂ treatment at 100 W for 120 seconds using an ashing apparatus ("NA1300", manufactured by ULVAC), and the oxygen ashing resistance was evaluated by measuring the film thickness difference before and after the treatment. The measured value of this film thickness difference is shown in Table 4 below. In addition, when this film thickness difference is less than 5 nm, oxygen ashing resistance can be evaluated as "A", when 5 nm or more and 8 nm or less, it is "B", and when it exceeds 8 nm, it can evaluate as "C".

<Formation of resist pattern>

[Examples 1 to 18]

Using the resist underlayer film-forming compositions (P-1) to (P-18) and the radiation-sensitive resin composition (J-1) shown in Table 4, according to the following method, as a contact hole pattern and a trench pattern as hole patterns Line and space patterns were formed, respectively, and the evaluation shown below was performed about each pattern. Table 4 shows the obtained evaluation results.

[Formation of Contact Hole Pattern]

After spin-coating an antireflection film forming material ("HM8006", manufactured by JSR) on the 12-inch silicon wafer, an antireflection film having a thickness of 100 nm was formed by performing PB (250 ° C, 60 seconds). A resist underlayer film having a thickness of 30 nm was formed by spin coating the resist underlayer film forming composition (P-1) on the antireflective film, PB (220 ° C., 60 seconds), and then cooling (23 ° C., 60 seconds). Subsequently, after spin-coating and PB (90 degreeC, 60 second) on the resist underlayer film in which the radiation sensitive resin composition (J-1) was formed, it cools (23 degreeC and 30 second), and forms the resist film of thickness 100nm. It was.

Subsequently, using an ArF immersion exposure apparatus ("S610C", manufactured by Nikon), reduction projection exposure was performed through a mask of 220 nm dot / 440 nm pitch under optical conditions of NA: 1.30 and Quadrupole. PEB (105 ° C., 60 seconds) is performed on a hot plate of the coating / developing device (“CLEAN TRACK Lithius Pro-i”, manufactured by Tokyo Electron), and cooled (23 ° C., 30 seconds). CLEAN TRACK Act 12 ”, manufactured by Tokyo Electron Co., Ltd.), was developed with puddle (30 seconds) using butyl acetate as a developer and rinsed with methyl isobutylcarbinol (MIBC). By spin-drying at 2,000 rpm for 15 seconds, the evaluation substrate in which the resist pattern of 55 nm hole / 110 nm pitch was formed was obtained.

[evaluation]

Using the evaluation board | substrate with which the said contact hole was formed, evaluation of the minimum hole dimension, CDU, and pattern shape was performed according to the following method. The scanning electron microscope ("CG-4000", the Hitachi High-Technology make) was used for the measurement and observation of the resist pattern of the evaluation board | substrate.

(Minimum hole dimension)

When obtaining the said board | substrate for evaluation, the exposure amount (mJ / cm <^2> ) which formed the resist pattern in which the diameter of a hole is 55 nm and the distance (space) between adjacent holes is 55 nm is made into the optimal exposure amount, Exposure was performed sequentially at large exposure amounts. At this time, since the diameter of the hole pattern obtained becomes small gradually, the non-opening of a resist pattern is observed with a certain exposure amount. Therefore, the hole size corresponding to the maximum exposure amount for which this non-opening pattern is not confirmed was defined as the minimum hole dimension (nm) to set the resolution index.

(CDU)

In the measurement of the minimum hole dimension, the diameter of the hole pattern having a diameter of 55 nm formed at the optimum exposure dose was measured for 24 lengths in total at arbitrary diameters, and 3σ values of the distribution degree of the 24 length measurement values in total were obtained as CDU. . In addition, CDU can be evaluated as "A" less than 2 nm, "B" in 2 nm or more and 3.5 nm or less, and "C" in the case where it exceeds 3.5 nm.

(Pattern shape)

In the above sensitivity, the cross-sectional shape of the hole pattern of 55 nm hole / 110 nm pitch formed in the resist film on the substrate was observed using a scanning electron microscope ("S-4800", manufactured by Hitachi High Technology), and the length was measured. It was. The length of the hole diameter Lb at the bottom of the resist pattern and the hole width La at the top of the resist pattern were measured, and the case within the range of 0.9≤ (La / Lb) ≤1.1 was defined as "A". B ”.

[Formation of Line and Space Pattern]

After spin-coating an antireflection film forming material ("HM8006", manufactured by JSR) on the 12-inch silicon wafer, an antireflection film having a thickness of 100 nm was formed by performing PB (250 ° C, 60 seconds). A resist underlayer film having a thickness of 30 nm was formed by spin coating the resist underlayer film forming composition (P-1) on the antireflective film, PB (220 ° C., 60 seconds), and then cooling (23 ° C., 60 seconds). Subsequently, after spin-coating and PB (90 degreeC, 60 second) on the resist underlayer film in which the radiation sensitive resin composition (J-1) was formed, it cools (23 degreeC and 30 second), and forms the resist film of thickness 100nm. It was.

Subsequently, an ArF liquid immersion exposure apparatus ("S610C", manufactured by Nikon) was used to expose through a mask of a mask size for 40 nm line / 80 nm pitch formation under an optical condition of NA: 1.30 and Dipole. PEB (100 ° C., 60 seconds) was carried out on the hot plate of “CLEAN TRACK Lithius Pro-i”, cooled (23 ° C., 30 seconds), puddle development (30 seconds) with butyl acetate as a developer, and rinsed with MIBC. It was. By spin-drying at 2,000 rpm for 15 seconds, the evaluation board | substrate with a resist pattern of 40 nm line / 80 nm pitch was obtained.

[evaluation]

Using the obtained evaluation board | substrate, the minimum collapse pre-dimension and pattern shape were evaluated in accordance with the following method. The scanning electron microscope ("CG-4000", the Hitachi High-Technology make) was used for the measurement and observation of the resist pattern of the evaluation board | substrate.

(Minimum collapse size)

When obtaining the said board | substrate for evaluation, the optimal exposure amount is made into the exposure amount (mJ / cm <^2> ) which formed the resist pattern which the line width of a line is 40 nm, and the distance (space) between adjacent lines is 40 nm. Exposure was performed sequentially at a smaller exposure amount in steps. At this time, since the line width of the pattern obtained becomes thinner gradually, collapse of a resist pattern is finally observed at the line width corresponding to a certain exposure amount. Therefore, the line width corresponding to the maximum exposure amount at which the collapse of the resist pattern is not confirmed was defined as the minimum pre-destruction dimension (nm) to set the index of pattern collapse resistance.

(Pattern shape)

The pattern shape evaluated "A" as the case where there is no trailing in the lower part of a resist pattern, and "B" when there was a pattern collapse or drag.

From the results of Table 4, by using the resist pattern forming method of the present invention, a resist having excellent resolution in contact hole pattern formation and pattern collapse resistance in CDU, line and space pattern formation, and pattern shape in both pattern formation It was found that a pattern was obtained. Moreover, according to the resist pattern formation method of this invention, it turned out that the characteristic of board | substrate reflectance, resist residue, and oxygen ashing resistance at the time of pattern formation can be provided.

<Matching evaluation of the composition for forming a resist underlayer film and a radiation sensitive resin composition>

The matching evaluation of the lithographic performance of the said composition for resist underlayer film formation and a radiation sensitive resin composition was performed about the combination of the composition for resist underlayer film formation and a radiation sensitive resin composition shown in Table 5. As shown below, after forming a resist underlayer film and a resist film, a contact hole pattern and a line and space pattern were formed, respectively, and each evaluation shown below was performed about each pattern. The obtained results are shown in Table 5.

[Examples 19 to 38]

[Formation of resist underlayer film and resist film]

In the same manner as in Examples 1 to 18, an antireflection film and a resist underlayer film were formed on a 12 inch silicon wafer. On this resist underlayer film, each radiation sensitive resin composition shown in following Table 5 was apply | coated by spin coating using said "CLEAN TRACK ACT 12", respectively, PB is performed at 80 degreeC on a hotplate for 60 second, and a film thickness is carried out. A resist film of 0.10 mu m was formed.

[Formation of Contact Hole Pattern]

The formed resist film was subjected to reduced projection exposure through an ArF liquid immersion exposure apparatus ("S610C", manufactured by Nikon, numerical aperture 1.30, Quadrupole) through a mask pattern of 216 nm dot / 416 nm pitch and immersion water. Subsequently, PEB was performed at the temperature shown in Table 5 for 60 seconds, followed by development at 23 ° C. for 30 seconds using n-butyl acetate as a developer, followed by rinsing for 10 seconds using MIBC, followed by drying to form a contact hole pattern. Formed. In addition, the exposure amount which becomes a hole pattern of diameter 60nm / 104nm pitch on a wafer after reduction projection was made into the optimal exposure amount, and this optimal exposure amount was made into the sensitivity (mJ / cm <^2> ).

[evaluation]

With respect to the obtained contact hole pattern, the depth of focus, the CDU, the minimum hole size, and the pattern shape were evaluated according to the following method.

(Depth of focus (DOF))

The contact hole pattern formed in the resist film on the substrate is exposed to the optimum exposure dose, and then the pattern size is within ± 10% using a pattern of 60 nm hole / 104 nm pitch and 60 nm hole / 800 nm pitch. DOF was obtained, and a common DOF area was obtained as DOF (unit: µm). In addition, the dimension measurement of a hole pattern was observed and performed from the upper part of a pattern using length measurement SEM ("CG4000", the Hitachi High-Technology make). Table 5 shows the measured values of DOF.

(CDU)

In the above sensitivity, the hole diameter was measured at an arbitrary 24 points for the 60 nm hole pattern formed in the resist film on the substrate, and the 3σ value indicating the distribution degree was defined as CDU. The results are shown in Table 5.

(Minimum hole dimension)

Using the dot pattern whose pattern pitch after reduction-projection exposure was 104 nm in diameter, it reduced-reduced projection exposure through immersion water, and when the exposure amount was enlarged, the minimum dimension of the hole obtained was measured and it was set as the minimum hole dimension. The results are shown in Table 5.

(Pattern shape)

In the above sensitivity, the cross-sectional shape of the hole pattern of 60 nm hole / 104 nm pitch formed in the resist film on the substrate was observed using a scanning electron microscope ("S-4800", manufactured by Hitachi High Technology), and the length was measured. It was. The length of the hole diameter Lb at the bottom of the resist pattern and the hole width La at the top of the resist pattern were measured, and the case within the range of 0.9≤ (La / Lb) ≤1.1 was defined as "A". Was evaluated.

[Formation of Line and Space Pattern]

An ArF liquid immersion exposure apparatus ("S610C", manufactured by Nikon) was exposed to the formed resist film through a mask having a mask size for 40 nm line / 80 nm pitch formation under an optical condition of NA: 1.30 and Dipole. After PEB was performed for 60 seconds on the PEB temperature shown in Tables 5-7 on the hot plate of said "CLEAN TRACK Lithius Pro-i", and cooled (23 degreeC, 30 second), puddle development was carried out using butyl acetate as a developing solution (30 seconds). ) And rinsed with MIBC. By spin-drying at 2,000 rpm for 15 seconds, the evaluation board | substrate with a resist pattern of 40 nm line / 80 nm pitch was obtained.

Using the obtained evaluation board, the minimum collapse pre-destruction dimension and the pattern shape were evaluated. The scanning electron microscope ("CG-4000", the Hitachi High Technology Corporation) was used for the measurement and observation of the resist pattern of this evaluation board | substrate.

(Minimum collapse size)

In the same manner as in the measurement method of the minimum pre-destruction size in Examples 1 to 18, the minimum pre-destruction size (nm) was measured and used as an index of pattern collapse resistance. The measured values before the minimum collapse are shown in Table 5 below.

(Pattern shape)

The pattern shape evaluated "A" as the case where there is no drag in the lower part of a resist pattern, and "B" when there was a pattern collapse or drag.

(When other developer is used)

Evaluation similar to the evaluation using the above-mentioned n-butyl acetate as a developing solution was performed using methyl-n-pentyl ketone or anisole developing solution as a developing solution. The evaluation results when the developer is methyl-n-pentyl ketone are shown in Table 6 below, and the evaluation results when the developer is Anisole are shown in Table 7 below.

[Comparative Examples 1 to 4]

[Formation of resist underlayer film and resist film]

Except having used the radiation sensitive resin composition shown in Table 5, it carried out similarly to the case of Examples 19-39, and formed the resist film on the resist underlayer film.

[Formation and Evaluation of Contact Hole Pattern and Line and Space Pattern]

The contact hole pattern and the line and space pattern were made in the same manner as in Examples 19 to 39 except that the PEB temperature shown in Table 5 was used as the PEB temperature, and a 2.38 mass% tetramethylammonium hydroxide aqueous solution was used as the developer. Formed. These formed patterns were evaluated in the same manner as in Examples 19 to 39. Table 5 shows the obtained evaluation results. In addition, the contact hole pattern formation could not be resolved in all cases, and "-" in Table 5 indicates that the above evaluation was not performed.

From the results of Tables 5 to 7, according to the resist pattern forming method of the present invention, when various organic solvents of ester, ketone, and ether are used as developer, both contact hole and line and space patterns have DOF, CDU, and resolution. It was found that a resist pattern having excellent pattern collapse resistance and pattern shape can be obtained. On the other hand, in the positive resist pattern formation method using the alkaline developer solution, the contact hole pattern formation could not be resolved. In line and space pattern formation, the pattern collapse resistance and the pattern shape were lower than in the resist pattern formation method of the present invention. It was also found that the degradation.

[Formation of Contact Hole Pattern by Multiple Opening Exposure]

The matching evaluation of the composition for resist underlayer film formation mentioned above and a radiation sensitive resin composition was performed about the case where a contact hole pattern is formed by performing exposure twice. About the combination of the resist underlayer film forming composition shown in Table 8, and a radiation sensitive resin composition, the contact hole pattern was formed and evaluated by the following method. The obtained results are shown in Table 8.

[Examples 40 to 47]

[Formation of Contact Hole Pattern]

NA = 1.3, Dipole Y using ArF liquid immersion exposure apparatus ("NSR-S610C", Nikon Seiki Company make) for the resist underlayer film and resist film formed by the method similar to Examples 19-39 mentioned above. When exposed through a mask for forming a 40 nm line / 80 nm pitch under optical conditions, the first reduced projection exposure is performed with an exposure amount (this exposure amount is used as a sensitivity) that becomes a 40 nm line / 80 nm pitch, followed by NA = 2, 2nd reduction projection exposure was performed with the exposure amount similar to 1st exposure so that a line may cross | intersect the exposure part which performed the 1st exposure on condition of Dipole X. After exposure, PEB was carried out on the hot plate of "CLEAN TRACK Lithius Pro i" at the PEB temperature shown in Table 8 for 60 seconds, cooled at 23 ° C. for 30 seconds, and puddle for 30 seconds using n-butyl acetate as a developer. Developed and rinsed with MIBC for 7 seconds. Thereafter, spin drying was performed by centrifugation at 2,000 rpm for 15 seconds to form a resist pattern having a 40 nm hole / 80 nm pitch.

[evaluation]

About the obtained contact hole pattern, DOF, CDU, minimum hole dimension, and pattern shape were evaluated in accordance with the following method.

(DOF)

For the resist pattern having a 40 nm hole / 80 nm pitch, the DOF of this pitch size and pattern size was determined. The dimension measurement of a resist pattern was observed and observed from the upper part of a pattern using length measurement SEM ("CG4000", the Hitachi High-Technology make). The measured value of DOF is shown in Table 8.

(CDU)

A resist pattern of 40 nm hole / 80 nm pitch was observed from the top of the pattern using a length measurement SEM ("CG4000", manufactured by Hitachi High Technology). The hole diameter was measured at arbitrary 24 points, the distribution degree of the measured value was calculated | required as 3σ, and it was set as CDU. The results are shown in Table 8.

(Minimum hole dimension)

Reduction of contact hole pattern by plural times of exposure With respect to the pattern whose pattern pitch after projected exposure becomes a 80 nm diameter pitch, the minimum dimension of the hole obtained when the exposure amount was increased was measured and resolution was evaluated. The measured value of the resolution is shown in Table 8.

(Pattern shape)

The cross-sectional shape of the resist pattern with a 40 nm hole / 80 nm pitch was observed, and a scanning electron microscope ("S-4800", Hitachi High-Technologies Corporation) was used to determine the hole diameter Lb and the resist pattern at the bottom of the resist pattern. The hole diameter La in the upper part was measured, and when it was 0.9 <= (La / Lb) <= 1.1, it evaluated as "A", and when it was outside this range, it evaluated as "B". Table 8 shows the evaluation results of the pattern shapes.

(When other developer is used)

In the above evaluation, the same evaluation was respectively performed using methyl n-amyl ketone or anisole instead of butyl acetate as a developing solution. The evaluation results are shown in Table 9 when the developer is methyl-n-pentyl ketone, and Table 10 when the anisole is respectively.

From the results of Tables 8 to 10, according to the resist pattern forming method of the present invention, even in the formation of contact holes by plural times of exposure, when various organic solvents of ester, ketone, and ether are used as developer, DOF, CDU, It was found that a resist pattern excellent in resolution and pattern shape can be obtained.

According to the resist pattern forming method of the present invention, it is possible to cope with the formation of various resist patterns such as trench patterns and hole patterns, and to form resist patterns excellent in various characteristics such as depth of focus, pattern shape, resolution, CDU, and pattern collapse resistance. can do. Therefore, the resist pattern formation method of this invention can be used suitably for the lithography technique which requires further refinement | miniaturization in the future.

Claims (8)

(1) A step of forming a resist underlayer film by applying the composition for forming a resist underlayer film containing [A] polysiloxane on a substrate;
(2) a step of forming a resist film by applying a radiation sensitive resin composition containing a polymer whose polarity is changed by the action of the [a1] acid to reduce its solubility in an organic solvent, on the resist underlayer film,
(3) exposing the resist film; and
(4) Process of developing the exposed resist film using a developing solution containing an organic solvent
Resist pattern forming method having a. The method of claim 1, wherein the resist underlayer film forming composition
[B] Nitrogen-Containing Compounds
It further contains a resist pattern forming method. The method of claim 1, wherein the resist underlayer film forming composition
[C] radiation-sensitive acid generators
It further contains a resist pattern forming method. The resist pattern forming method according to claim 1, wherein the polymer [a1] is a polymer having a structural unit (I) represented by the following general formula (1).
&Lt; Formula 1 >

R is a hydrogen atom or a methyl group, and R ^p1 , R ^p2 and R ^p3 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms, provided that R ^p2 and R ^p3 are bonded to each other, May form together with a carbon atom a divalent alicyclic hydrocarbon group having 4 to 20 carbon atoms) The method of claim 1, wherein the radiation-sensitive resin composition
[a2] A polymer having at least one structural unit (III) selected from the group consisting of structural units represented by formula (3-1) and structural units represented by formula (3-2)
It further contains a resist pattern forming method.

(In formula (3-1), R <^1> is a hydrogen atom, a methyl group, or a trifluoromethyl group, R <^2> is a C1-C6 linear or branched alkyl group which has a fluorine atom, or C4 which has a fluorine atom. To a monovalent alicyclic hydrocarbon group of 20, provided that some or all of the hydrogen atoms of the alkyl group and the alicyclic hydrocarbon group may be substituted)

(In formula (3-2), R <^3> is a hydrogen atom, a methyl group, or a trifluoromethyl group, R <^4> is a (m + 1) valent coupling group, m is an integer of 1-3, and X has a fluorine atom. A divalent linking group and R ⁵ is a hydrogen atom or a monovalent organic group, provided that when m is 2 or 3, a plurality of X and R ⁵ may be the same or different, respectively) The method of claim 5, wherein the polymer [a2] is a polymer having no acid dissociable group. The method of claim 1, wherein the polysiloxane [A] is a hydrolysis condensate of a silane compound represented by the following general formula (i).

(In Formula (i), R ^A is a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group, an aryl group or a cyano group, and part or all of the hydrogen atoms of the alkyl group are glycidyloxy groups and oxetas. May be substituted with a silyl group, an acid anhydride group or a cyano group, and some or all of the hydrogen atoms of the aryl group may be substituted with a hydroxyl group, X is a halogen atom or -OR ^B , provided that R ^B is Monovalent organic group, a being an integer of 0 to 3, provided that when R ^A and X are each plural, a plurality of R ^A and X may be the same or different.) The resist pattern formation method of any one of Claims 1-7 which forms at least 1 sort (s) of pattern chosen from the group which consists of a trench pattern and a hole pattern.